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                                                                     Exhibit 4.3

                               MARKEL CORPORATION
                                     ISSUER

                                       AND

                            THE CHASE MANHATTAN BANK
                                     TRUSTEE

                                    INDENTURE

                         DATED AS OF __________ __, 200_


                         JUNIOR SUBORDINATED DEBENTURES

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                             CROSS REFERENCE TABLE*


          SECTION OF TRUST
          INDENTURE ACT OF                                     SECTION OF
          1939, AS AMENDED                                      AGREEMENT
          ----------------                                      ---------

               310(A) .................................       6.3, 7.8
               310(B) .................................   INAPPLICABLE
               310(C) .................................   INAPPLICABLE
               311(A) .................................       2.2, 5.1
               311(B) .................................   INAPPLICABLE
               311(C) .................................   INAPPLICABLE
               312(A) .................................   INAPPLICABLE
               312(B) .................................   INAPPLICABLE
               312(C) .................................   INAPPLICABLE
               313(A) .................................  2.3, 5.3, 5.4
               313(B) .................................   INAPPLICABLE
               313(C) .................................   INAPPLICABLE
               313(D) .................................   INAPPLICABLE
               314(A) .................................            2.4
               314(B) .................................   INAPPLICABLE
               314(C) .................................            2.6
               314(D) .................................   INAPPLICABLE
               314(E) .................................   INAPPLICABLE
               314(F) .................................   INAPPLICABLE
               315(A) .................................   INAPPLICABLE
               315(B) .................................   INAPPLICABLE
               315(C) .................................   INAPPLICABLE
               315(D) .................................            2.7
               316(A) .................................  2.6; 9.3; 9.6
               316(B) .................................   INAPPLICABLE
               316(C) .................................       6.6, 7.5
               317(A) .................................   INAPPLICABLE
               317(B) .................................            6.5
               318(A) .................................           10.6

_________

         * THIS CROSS-REFERENCE TABLE DOES NOT CONSTITUTE PART OF THE AGREEMENT
AND SHALL NOT HAVE ANY BEARING UPON THE INTERPRETATION OF ANY OF ITS TERMS OR
PROVISIONS.

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                                TABLE OF CONTENTS

<TABLE>
<S>                                                                                                              <C>
ARTICLE I  DEFINITIONS..........................................................................................    1
   1.1   Certain Terms Defined..................................................................................    1
ARTICLE II ISSUE, DESCRIPTION, EXECUTION, REGISTRATION OF TRANSFER AND EXCHANGE OF SECURITIES...................    9
   2.1   Amount, Series and Delivery of Securities..............................................................    9
   2.2   Form of Securities and Trustee's Certificate...........................................................   12
   2.3   Denominations of and Payment of Interest on Securities.................................................   13
   2.4   Execution of Securities................................................................................   14
   2.5   Registration, Transfer and Exchange of Securities......................................................   14
   2.6   Temporary Securities...................................................................................   16
   2.7   Mutilated, Destroyed, Lost or Stolen Securities........................................................   16
   2.8   Cancellation and Destruction of Surrendered Securities.................................................   17
   2.9   Authenticating Agents..................................................................................   17
   2.10  Deferrals of Interest Payment Dates....................................................................   18
   2.11  Right of Set-Off.......................................................................................   18
   2.12  Shortening or Extension of Stated Maturity.............................................................   18
   2.13  Agreed Tax Treatment...................................................................................   18
   2.14  CUSIP Numbers..........................................................................................   19
ARTICLE III REDEMPTION OF SECURITIES............................................................................   19
   3.1   Applicability of Article...............................................................................   19
   3.2   Mailing of Notice of Redemption........................................................................   19
   3.3   When Securities Called for Redemption Become Due and Payable...........................................   20
ARTICLE IV PARTICULAR COVENANTS OF THE COMPANY..................................................................   21
   4.1   Payment of Principal of and Interest On Securities.....................................................   21
   4.2   Maintenance of Offices or Agencies for Registration of Transfer, Exchange and Payment of Securities....   21
   4.3   Appointment to Fill a Vacancy in the Office of Trustee.................................................   21
   4.4   Duties of Paying Agent.................................................................................   21
   4.5   OFFICERS' CERTIFICATE AS TO DEFAULTS; NOTICES OF CERTAIN...............................................   22
   4.6   Waiver of Covenants....................................................................................   22
   4.7   ADDITIONAL TAX SUMS....................................................................................   22
   4.8   Additional Covenants...................................................................................   23
   4.9   Calculation of Original Issue Discount.................................................................   23
   4.10  Calculation of Original Issue Discount.................................................................   23
ARTICLE V SECURITYHOLDERS' LISTS AND REPORTS BY THE COMPANY  AND THE TRUSTEE....................................   24
   5.1   Company to Furnish Trustee Information as to the Names and Addresses of Securityholders................   24
   5.2   Trustee to Preserve Information as to the Names and Addresses of Securityholders Received by It........   24
   5.3   Annual and Other Reports to be Filed by Company With Trustee...........................................   24
   5.4   Trustee to Transmit Annual Report to Securityholders...................................................   25
ARTICLE VI REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON EVENT OF DEFAULT......................................   25
   6.1   Events of Default Defined..............................................................................   25
   6.2   Covenant of Company to Pay to Trustee Whole Amount Due On Securities On Default in Payment of Interest
         or Principal...........................................................................................   27
   6.3   Application of Moneys Collected by Trustee.............................................................   28
   6.4   Limitation On Suits by Holders of Securities...........................................................   29
   6.5   On Default Trustee May Take Appropriate Action; Direct Action..........................................   29
</TABLE>

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<TABLE>
<S>                                                                                                               <C>
   6.6   Rights of Holders of Majority in Principal Amount of Securities to Direct Trustee and to Waive Default..  30
   6.7   Trustee to Give Notice of Defaults Known to It, but May Withhold in Certain Circumstances...............  30
   6.8   Requirement of an Undertaking to Pay Costs in Certain Suits Under the Indenture or Against the Trustee..  31
ARTICLE VII CONCERNING THE TRUSTEE...............................................................................  31
   7.1   Upon Event of Default Occurring and Continuing, Trustee Shall Exercise Powers Vested in It, and Use Same
         Degree of Care and Skill in Their Exercise, as a Prudent Man Would Use..................................  31
   7.2   Reliance on Documents, Opinions, Etc.  Except as otherwise Provided in Section 7.1......................  32
   7.3   Trustee Not Liable for Recitals in Indenture or in Securities...........................................  33
   7.4   May Hold Securities.....................................................................................  33
   7.5   Moneys Received by Trustee to be Held in Trust Without Interest.........................................  33
   7.6   Trustee Entitled to Compensation, Reimbursement and Indemnity...........................................  33
   7.7   Right of Trustee to Rely on Officers' Certificate Where No Other Evidence Specifically Prescribed.......  33
   7.8   Disqualification; Conflicting Interests.................................................................  34
   7.9   Requirements for Eligibility of Trustee.................................................................  34
   7.10  Resignation and Removal of Trustee......................................................................  34
   7.11  Acceptance by Successor Trustee.........................................................................  35
   7.12  Successor to Trustee by Merger, Consolidation or Succession to Business.................................  36
   7.13  Limitations on Preferential Collection of Claims by the Trustee.........................................  36
ARTICLE VIII CONCERNING THE SECURITYHOLDERS......................................................................  36
   8.1   Evidence of Action by Securityholders...................................................................  36
   8.2   Proof of Execution of Instruments and of Holding of Securities..........................................  37
   8.3   Who May be Deemed Owners of Securities..................................................................  37
   8.4   Securities Owned by Company or Controlled or Controlling Persons Disregarded for Certain Purposes.......  37
   8.5   Instruments Executed by Securityholders Bind Future Holders.............................................  38
ARTICLE IX SECURITYHOLDERS' MEETINGS.............................................................................  38
   9.1   Purposes for which Meetings may be Called...............................................................  38
   9.2   Manner of Calling Meetings..............................................................................  38
   9.3   Call of Meeting by Company or Securityholders...........................................................  38
   9.4   Who May Attend and Vote at Meetings.....................................................................  39
   9.5   Regulations may be made by Trustee......................................................................  39
   9.6   Manner of Voting at Meetings and Record to be Kept......................................................  39
   9.7   Exercise of Rights of Trustee, Securityholders and Holders of Preferred Securities Not to be Hindered or
         Delayed.................................................................................................  40
ARTICLE X SUPPLEMENTAL INDENTURES................................................................................  40
   10.1  Purposes for which Supplemental Indentures may be Entered into Without Consent of Securityholders.......  40
   10.2  Modification of Indenture with Consent of Holders of a Majority in Principal Amount of Securities.......  41
   10.3  Effect of Supplemental Indentures.......................................................................  42
   10.4  Securities May Bear Notation of Changes by Supplemental Indentures......................................  42
   10.5  Revocation and Effect of Consents.......................................................................  43
   10.6  Conformity with Trust Indenture Act.....................................................................  43
ARTICLE XI CONSOLIDATION, MERGER, SALE OR CONVEYANCE.............................................................  43
   11.1  Company May Consolidate, Etc., Only on Certain Terms....................................................  43
   11.2  Successor Person Substituted for Company................................................................  43
ARTICLE XII SATISFACTION AND DISCHARGE OF INDENTURE, UNCLAIMED MONEYS............................................  44
   12.1  Satisfaction and Discharge of Indenture.................................................................  44
</TABLE>

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<TABLE>
<S>                                                                                                                <C>
   12.2     Application by Trustee of Funds Deposited for Payment of Securities..................................   44
   12.3     Repayment of Moneys Held by Paying Agent.............................................................   44
   12.4     Repayment of Moneys Held by Trustee..................................................................   44
ARTICLE XIII IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS,  DIRECTORS AND EMPLOYEES.........................   45
   13.1     Incorporators, Stockholders, Officers, Directors and Employees of Company Exempt from Individual
            Liability............................................................................................   45
ARTICLE XIV SUBORDINATION OF SECURITIES..........................................................................   45
   14.1     Agreement to Subordinate.............................................................................   45
   14.2     Obligation of the Company Unconditional..............................................................   46
   14.3     Limitations on Duties to Holders of Senior Indebtedness of the Company...............................   47
   14.4     Notice to Trustee of Facts Prohibiting Payment.......................................................   47
   14.5     Application by Trustee of Moneys Deposited with It...................................................   47
   14.6     Subrogation..........................................................................................   47
   14.7     Subordination Rights Not Impaired by Acts or Omissions of Company or Holders of Senior Indebtedness
            of the Company.......................................................................................   47
   14.8     Authorization of Trustee to Effectuate Subordination of Securities...................................   48
   14.9     No Payment when Senior Indebtedness in Default.......................................................   48
   14.10    Right of Trustee to Hold Senior Indebtedness of the Company..........................................   48
   14.11    Article Fourteen Not to Prevent Defaults.............................................................   48
ARTICLE XV MISCELLANEOUS PROVISIONS..............................................................................   48
   15.1     Successors and Assigns of Company Bound by Indenture.................................................   49
   15.2     Acts of Board, Committee or Officer of Successor Corporation Valid...................................   49
   15.3     Required Notices or Demands may be Served by Mail....................................................   49
   15.5     Payments Due on Saturdays, Sundays, and Holidays.....................................................   49
   15.6     Provisions Required by Trust Indenture Act of 1939 to Control........................................   49
   15.7     Indenture and Securities to be Construed in Accordance with the Laws of the State of New York........   49
   15.8     Provisions of the Indenture and Securities for the Sole Benefit of the Parties and the
            Securityholders......................................................................................   49
   15.9     Indenture May be Executed in Counterparts............................................................   50
   15.10    Securities in Foreign Currencies.....................................................................   50
   15.11    Table of Contents, Headings, Etc.....................................................................   50
</TABLE>

                                        i

<PAGE>

         THIS INDENTURE, dated as of the ___ day of ________, 200_ between
MARKEL CORPORATION, a corporation duly organized and existing under the laws of
the Commonwealth of Virginia (hereinafter sometimes referred to as the
"Company"), and THE CHASE MANHATTAN BANK, a banking corporation duly organized
and existing under the laws of the State of New York (hereinafter sometimes
referred to as the "Trustee").

                                   WITNESSETH:

         WHEREAS, for its lawful corporate purposes, the Company has duly
authorized the issuance from time to time of its unsecured junior subordinated
debentures or other evidences of indebtedness (hereinafter referred to as the
"Securities"), without limit as to principal amount, issuable in one or more
series, the amount and terms of each such series to be determined as hereinafter
provided, including, without limitation, Securities issued to evidence loans
made to the Company of the proceeds from the issuance from time to time by one
or more business trusts, whether existing on the date hereof or hereafter
created, (each a "Markel Capital Trust," and collectively, the "Markel Capital
Trusts") of preferred interests in such Trusts, having the rights provided for
in such Trusts (the "Preferred Securities" which may also be referred to,
without limitation, as the "Capital Securities") and common interests in such
Trusts, having the rights provided for in such Trusts (the "Common Securities,"
and collectively with the Preferred Securities, the "Trust Securities"); to be
authenticated by the Trustee; and, to provide the terms and conditions upon
which the Securities are to be authenticated, issued and delivered, the Company
has duly authorized the execution of this Indenture; and

         WHEREAS, all acts and things necessary to make the Securities when
executed by the Company and authenticated and delivered by the Trustee as in
this Indenture provided, the valid, binding and legal obligations of the
Company, and to constitute these presents a valid indenture and agreement
according to its terms, have been done and performed and the execution of this
Indenture and the issue hereunder of the Securities have in all respects been
duly authorized, and the Company, in the exercise of the legal rights and power
vested in it, executes this Indenture and proposes to make, execute, issue and
deliver the Securities;

         NOW, THEREFORE, in order to declare the terms and conditions upon which
the Securities are authenticated, issued and delivered, and in consideration of
the premises and of the purchase and acceptance of the Securities by the holders
thereof, the Company covenants and agrees with the Trustee, for the equal and
proportionate benefit of the respective holders from time to time of the
Securities or of series thereof, as follows:

                                    ARTICLE I
                                   DEFINITIONS

         1.1      Certain Terms Defined. For all purposes of this Indenture,
except as otherwise expressly provided or unless the context otherwise requires:

                  (a) The terms defined in this Article have the meanings
assigned to them in this Article, and include the plural as well as the
singular;

                  (b) All other terms used herein which are defined in the Trust
Indenture Act of 1939, whether directly or by reference therein, have the
meanings assigned to them therein (except as otherwise expressly provided);

                  (c) All accounting terms used herein and not expressly defined
herein shall have the meanings assigned to them in accordance with generally
accepted accounting principles in the United States of America, and, except as
otherwise herein expressly provided, the term "generally accepted accounting
principles" with respect to any computation required or permitted hereunder
shall mean such accounting principles as are generally accepted in the United
States of America at the date of such computation; provided, that when two or
more principles are so generally accepted, it shall mean that set of principles
consistent with those in use by the Company; and

                  (d) The terms "herein," "hereof" and "hereunder" and other
words of similar import refer to this Indenture as a whole and not to any
particular Article, Section or other subdivision.

<PAGE>

Additional Interest:

         The term "Additional Interest" means the interest, if any, that shall
accrue on any interest on the Securities of any series the payment of which has
not been made on the applicable interest payment date and which shall accrue at
the rate per annum specified or determined as specified in such Security.

Additional Tax Sums:

         The term "Additional Tax Sums" has the meaning specified in Section
4.7.

Administrative Trustee:

         The term "Administrative Trustee" means, in respect of any Markel
Capital Trust, each Person identified as an "Administrative Trustee" in the
related Trust Agreement, solely in such Person's capacity as Administrative
Trustee of such Markel Capital Trust under such Trust Agreement and not in such
Person's individual capacity, or any successor administrative trustee appointed
as therein provided.

Authenticating Agent:

         The term "Authenticating Agent" means any Authenticating Agent
appointed by the Trustee pursuant to Section 2.9.

Authorized Newspaper:

         The term "Authorized Newspaper" means a newspaper in an official
language of the place of publication or in the English language, customarily
published at least once a day for at least five days in each calendar week,
except days that are legal holidays in the relevant place of publication and of
general circulation in each place in connection with which the term is used or
in the financial community of each such place. Whenever successive publications
are required to be made in an Authorized Newspaper, the successive publications
may be made in the same or in a different newspaper meeting the foregoing
requirements and in each case on any day of the week. If it is impossible or, in
the opinion of the Trustee, impracticable to publish any notice in the manner
herein provided, then such publication in lieu thereof as shall be made with the
approval of the Trustee shall constitute a sufficient publication of such
notice.

Board of Directors:

         The term "Board of Directors," when used with reference to the Company,
means the Board of Directors of the Company or any other committee of or created
by the Board of Directors of the Company duly authorized to act hereunder.

Business Day:

         The term "Business Day" means any day which is not a Saturday or Sunday
or a day on which banking institutions in the place of payment or other location
are authorized or required by law or executive order to close or a day on which
the principal corporate trust office of the Trustee or the Property Trustee is
closed for business.

Capital Securities:

         The term "Capital Securities" has the meaning specified in the recitals
to this Indenture.

Capital Stock:

                                        2

<PAGE>

         The term "Capital Stock" means shares of capital stock of any class of
any corporation whether now or hereafter authorized regardless of whether such
capital stock shall be limited to a fixed sum or percentage in respect of the
rights of the holders thereof to participate in dividends and in the
distribution of assets upon any voluntary or involuntary liquidation,
dissolution or winding up.

Commission:

         The term "Commission" means the Securities and Exchange Commission, as
from time to time constituted, created under the Exchange Act, or, if at any
time after the execution of this instrument such Commission is not existing and
performing the duties now assigned to it under the Trust Indenture Act of 1939,
then the body performing such duties on such date.

Common Securities:

         The term "Common Securities" has the meaning specified in the recitals
to this Indenture.

Common Stock:

         The term "Common Stock" means the common shares, no par value, of the
Company.

Company:

         The term "Company" means Markel Corporation, a corporation duly
organized and existing under the laws of the Commonwealth of Virginia and,
subject to the provisions of Article Eleven, shall also include its successors
and assigns.

Depositary:

         The term "Depositary" means, with respect to the Securities of any
series issuable or issued in whole or in part in the form of one or more global
Securities, the person designated as Depositary by the Company pursuant to
Section 2.1 until a successor Depositary shall have become such pursuant to the
applicable provisions of this Indenture, and thereafter the term "Depositary"
shall mean or include each person who is then a Depositary hereunder and if at
any time there is more than one such person, the term "Depositary" as used with
respect to the Securities of any series shall mean the Depositary with respect
to the Securities of such series.

Distributions:

         The term "Distributions," with respect to the Trust Securities issued
by a Markel Capital Trust, means amounts payable in respect of such Trust
Securities as provided in the related Trust Agreement and referred to therein as
"Distributions."

Markel Guarantee:

         The term "Markel Guarantee" means the guarantee by the Company of
distributions on the Preferred Securities of a Markel Capital Trust to the
extent provided in the Guarantee Agreement (as defined in the related Trust
Agreement).

                                        3

<PAGE>

Markel Capital Trust:

         The terms "Markel Capital Trust" and "Markel Capital Trusts" each have
the meaning specified in the recitals to this Indenture.

Event of Default:

         The term "Event of Default" with respect to Securities of any series
shall mean any event specified as such in Section 6.1 and any other event as may
be established with respect to the Securities of such series as contemplated by
Section 2.1.

Exchange Act:

         The term "Exchange Act" has the meaning specified in Section 2.2.

Extension Period:

         The term "Extension Period" has the meaning specified in Section 2.10.

Indenture:

         The term "Indenture" means this instrument as originally executed, or,
if amended or supplemented as herein provided, then as so amended or
supplemented, and shall include the form and terms of particular series of
Securities established as contemplated by Sections 2.1 and 2.2.

Investment Company Event:

         The term "Investment Company Event" means in respect of a Markel
Capital Trust, the receipt by the Company and a Markel Capital Trust of an
Investment Company Event Opinion (as defined in the relevant Trust Agreement) to
the effect that, as a result of the occurrence of a change in law or regulation
or a change in interpretation or application of law or regulation by any
legislative body, court, governmental agency or regulatory authority (a "Change
in 1940 Act Law"), such Markel Capital Trust is or will be considered an
investment company that is required to be registered under the 1940 Act, which
Change in 1940 Act Law becomes effective on or after the date of original
issuance of the Preferred Securities of such Markel Capital Trust.

Maturity:

         The term "Maturity" when used with respect to any Security means the
date on which the principal of such Security becomes due and payable as therein
or herein provided, whether at the Stated Maturity or by declaration of
acceleration, call for redemption or otherwise.

1940 Act:

         The term "1940 Act" means the Investment Company Act of 1940, as
amended.

Officers' Certificate:

         The term "Officers' Certificate" shall mean a certificate signed by any
two of the Chairman of the Board, the President, any Vice President, the
Treasurer, the Controller or the Corporate Secretary, an Assistant Treasurer or
an Assistant Corporate Secretary and delivered to the Trustee. Each such
certificate shall include the statements

                                        4

<PAGE>

provided for in Section 15.4, if and to the extent required by the provisions
thereof and will comply with Section 314 of the Trust Indenture Act of 1939.

Opinion of Counsel:

         The term "Opinion of Counsel" shall mean a written opinion of counsel,
who may be an employee of or counsel for the Company or other counsel who shall
be reasonably satisfactory to the Trustee. Each such opinion shall, if required
by the Trust Indenture Act, comply with the requirements of Section 314 of the
Trust Indenture Act.

Original Issue Date:

         The term "Original Issue Date" means the first date of issuance of each
Security.

Original Issue Discount Security:

         The term "Original Issue Discount Security" shall mean any Security
which provides for an amount less than the principal amount thereof to be due
and payable upon declaration pursuant to Section 6.1.

Paying Agent:

         The term "Paying Agent" means any Person or Persons authorized by the
Company to pay the principal or interest on any Securities on behalf of the
Company.

Person:

         The term "Person" or "person" means any individual, corporation,
estate, partnership, joint venture, association, joint stock company, limited
liability company, trust, unincorporated association or government or any agency
or political subdivision thereof, or any other entity of whatever nature.

Preferred Securities:

         The term "Preferred Securities" has the meaning specified in the
recitals to this Indenture.

Principal:

         The term "principal," whenever used with reference to the Securities or
any Security or any portion thereof, shall be deemed to include "and premium, if
any."

Property Trustee:

         The term "Property Trustee" means, in respect of any Markel Capital
Trust, the commercial bank or trust company identified as the "Property Trustee"
in the related Trust Agreement, solely in its capacity as Property Trustee of
such Markel Capital Trust under such Trust Agreement and not in its individual
capacity, or its successor in interest in such capacity, or any successor
property trustee appointed as therein provided.

Ranking Junior to the Securities:

         The term "ranking junior to the Securities" means with respect to the
Company and its Subsidiaries, any other obligation which (a) ranks junior to and
not equally with or prior to the Securities (or any other obligations ranking on
a parity with the Securities) in right of payment upon the happening of any
event of the kind specified in

                                        5

<PAGE>

the first sentence of the second paragraph of Section 14.1, or (b) is
specifically designated as ranking junior to the Securities by express provision
in the instrument creating or evidencing such obligation.

         The securing of any obligations, otherwise ranking junior to the
Securities, shall be deemed to prevent such obligations from constituting
obligations ranking junior to the Securities.

Ranking on a parity with the Securities:

         The term "ranking on a parity with the Securities" means with respect
to the Company and its Subsidiaries, any other obligation which (a) ranks
equally with and not prior to the Securities in right of payment upon the
happening of any event of the kind specified in the first sentence of the second
paragraph of Section 14.1, (b) any Markel Guarantee of Preferred Securities of
any Markel Capital Trust or other entity affiliated with the Company that is a
financing entity of the Company, or (c) is specifically designated as ranking on
a parity with the Securities by express provision in the instrument creating or
evidencing such obligation.

         The securing of any obligations, otherwise ranking on a parity with the
Securities, shall not be deemed to prevent such obligations from constituting
obligations ranking on a parity with the Securities.

Record date:

         The term "record date" has the meaning specified in Section 2.3.

Redemption; redeem; redeemable; etc.:

         The terms "redemption," "redeem" and "redeemable" when used with
respect to any Security, shall include, without limitation, any prepayment or
repayment provisions applicable to such Security.

Register:

         The term "Register" has the meaning specified in Section 2.5.

Resolution of the Company:

         The term "Resolution of the Company" means a resolution of the Company,
in the form of a resolution of the Board of Directors, in the form of a
resolution of a duly constituted committee of the Board of Directors, or in the
form of a resolution of two or more senior officers of the Company, authorizing,
ratifying, setting forth or otherwise validating agreements, execution and
delivery of documents, the issuance, form and terms of Securities, or any other
actions or proceedings pursuant or with respect to this Indenture.

Responsible Officer:

         The term "Responsible Officer," when used with respect to the Trustee,
means any officer of the Trustee with direct responsibility for the
administration of this Indenture, and also any other officer to whom any
corporate trust matter is referred because of his knowledge of, and familiarity
with, a particular subject.

Rights Plan:

         The term "Rights Plan" means a plan of the Company providing for the
issuance by the Company to all holders of its Common Stock of rights entitling
the holders thereof to subscribe for or purchase shares of Common Stock or any
class or series of preferred stock, which rights (i) are deemed to be
transferred with such shares of

                                        6

<PAGE>

Common Stock, (ii) are not exercisable and (iii) are also issued in respect of
future issuances of Common Stock, in each case until the occurrence of a
specified event or events.

Security or Securities; outstanding:

         The term "Security" or "Securities" means any security or securities of
the Company, as the case may be, without regard to series, authenticated and
delivered under this Indenture.

         The term "outstanding," when used with reference to Securities and
subject to the provisions of Section 8.4, means as of any particular time, all
Securities authenticated and delivered by the Trustee under this Indenture,
except

               (a)  Securities theretofore canceled by the Trustee or delivered
to the Trustee for cancellation;

               (b)  Securities, or portions thereof, for the payment or
redemption of which moneys in the necessary amount shall have been deposited in
trust with the Trustee or with any Paying Agent (other than the Company) or
shall have been set aside and segregated in trust by the Company (if the Company
shall act as its own Paying Agent), provided that such Securities shall have
reached their Stated Maturity or, if such Securities are to be redeemed prior to
the Stated Maturity thereof, notice of such redemption shall have been given as
in Article Three provided, or provision satisfactory to the Trustee shall have
been made for giving such notice; and

               (c)  Securities in lieu of or in substitution for which other
Securities shall have been authenticated and delivered or which have been paid
pursuant to the terms of Section 2.7 unless proof satisfactory to the Trustee is
presented that any such Securities are held by a protected purchaser (as defined
in Article 8 of the Uniform Commercial Code) in whose hands any of such
Securities is a valid, binding and legal obligation of the Company.

         In determining whether the holders of the requisite principal amount of
outstanding Securities have given any request, demand, authorization, direction,
notice, consent or waiver hereunder, the principal amount of an Original Issue
Discount Security that shall be deemed to be outstanding for such purposes shall
be the amount of the principal thereof that would be due and payable as of the
date of such determination upon a declaration of acceleration of the Maturity
thereof pursuant to Section 6.1.

Securityholder; registered holder:

         The terms "Securityholder," "holder of Securities," "registered holder"
or other similar term, mean any person who shall at the time be the registered
holder of any Security or Securities on the Register kept for that purpose in
accordance with the provisions of this Indenture.

Senior Indebtedness of the Company:

         The term "Senior Indebtedness of the Company" means with respect to the
Company and its Subsidiaries (i) any indebtedness for borrowed or purchased
money, whether or not evidenced by bonds, debentures, notes or other written
instruments, (ii) obligations for reimbursement under letters of credit,
banker's acceptances, security purchase facilities or similar facilities, (iii)
any indebtedness or other obligations with respect to commodity contracts
(including but not limited to contracts in the spot, forward and futures
markets, options, and contracts for differences), interest rate commodity and
currency swap agreements, cap, floor and collar agreements, currency spot and
forward contracts, and other similar agreements or arrangements designed to
protect against fluctuations in commodity prices, currency exchange or interest
rates, (iv) all obligations as lessee which are capitalized in accordance with
generally accepted accounting principles, and (v) any guarantees, endorsements
(other than by endorsement of negotiable instruments for collection in the
ordinary course of business) or other similar contingent obligations in respect
of obligations of others of a type described in (i), (ii) or (iii) above,
whether or not such

                                        7

<PAGE>

obligation is classified as a liability on a balance sheet prepared in
accordance with generally accepted accounting principles, in each case listed in
(i), (ii), (iii), (iv) and (v) above whether outstanding on the date of
execution of this Indenture or thereafter incurred, other than obligations
ranking on a parity with the Securities or ranking junior to the Securities.

Stated Maturity:

         The term "Stated Maturity" when used with respect to any Security or
any installment of principal thereof or interest thereon means the date
specified pursuant to the terms of such Security as the date on which the
principal of such Security or such installment of interest is due and payable in
the case of such principal, as such date may be shortened or extended as
provided pursuant to the terms of such Security and this Indenture.

Subsidiary:

         The term "Subsidiary" means any corporation(or the equivalent type of
entity in other jurisdictions) more than 50% of the outstanding voting stock of
which is owned, directly or indirectly, by the Company or by one or more other
Subsidiaries, or by the Company and one or more other Subsidiaries. For the
purposes of this definition, "voting stock" means stock which ordinarily has
voting power for the election of directors, whether at all times or only so long
as no senior class of stock has such voting power by reason of any contingency.

Tax Event:

         The term "Tax Event" means the receipt by the Company and a Markel
Capital Trust of a Tax Event Opinion (as defined in the relevant Trust
Agreement) to the effect that, as a result of any amendment to, or change
(including any announced prospective change) in, the laws (or any regulations
thereunder) of the United States or any political subdivision or taxing
authority thereof or therein, or as a result of any official administrative
written decision or pronouncement or judicial decision interpreting or applying
such laws or regulations, which amendment or change is effective or which
pronouncement or decision is announced on or after the date of issuance of the
Preferred Securities of such Markel Capital Trust, there is more than an
insubstantial risk that (i) the Markel Capital Trust is, or will be within 90
days after the date of such Tax Event Opinion, subject to United States federal
income tax with respect to income received or accrued on the corresponding
series of Securities issued by the Company to such Markel Capital Trust, (ii)
interest payable by the Company on such corresponding series of Securities is
not, or within 90 days of the date of such Tax Event Opinion, will not be,
deductible by the Company, in whole or in part, for United States federal income
tax purposes, or (iii) the Markel Capital Trust is, or will be within 90 days
after the date of such Tax Event Opinion, subject to more than a de minimis
amount of other taxes, duties or other governmental charges.

Trust Agreement:

         The term "Trust Agreement" means the Trust Agreement governing any
Markel Capital Trust, whether now existing or created in the future, which
purchased the Securities of any series in each case.

Trustee; Principal Office of the Trustee:

         The term "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument, and, subject to the provisions of Article Seven,
shall also include its successors. The term "principal office" of the Trustee
shall mean the principal corporate trust office of the Trustee in the City of
New York, at which the corporate trust business of the Trustee shall, at any
particular time, be principally administered. The present address of the office
at which the corporate trust business of the Trustee is administered is 450 West
33rd Street, New York, New York 10001 (Attention: Institutional Trust Services).

Trust Indenture Act of 1939:

                                        8

<PAGE>

         Except as herein otherwise expressly provided or unless the context
requires otherwise, the term "Trust Indenture Act of 1939" shall mean the Trust
Indenture Act of 1939, as amended by the Trust Indenture Reform Act of 1990, as
in force at the date as of which this Indenture was originally executed;
provided, however, that, in the event that the Trust Indenture Act is amended
after such date, then "Trust Indenture Act of 1939" means, to the extent
required by any such amendment, the Trust Indenture Act of 1939 as so amended.

Trust Securities:

         The term "Trust Securities" has the meaning specified in the recitals
to this Indenture.

Vice President:

         The term "Vice President", when used with respect to the Company or the
Trustee, means any vice president, whether or not designated by a number or a
word or words added before or after the title "Vice President."

                                   ARTICLE II
             ISSUE, DESCRIPTION, EXECUTION, REGISTRATION OF TRANSFER
                           AND EXCHANGE OF SECURITIES

         2.1   Amount,  Series and Delivery of Securities.  The aggregate
principal amount of Securities which may be authenticated and delivered under
this Indenture is unlimited.

         The Securities may be issued in one or more series. The terms of each
series (which terms shall not be inconsistent with the provisions of this
Indenture), shall either be established in or pursuant to a Resolution of the
Company and set forth in an Officers' Certificate, or set forth in one or more
indentures supplemental hereto, prior to the issuance of Securities of any
series and shall specify:

               (a)  The title of the Securities of such series (which shall
distinguish the Securities of the series from all other Securities and which
shall include the word "subordinated" or a word of like meaning);

               (b)  Any limit upon the aggregate principal amount of the
Securities of such series which may be executed, authenticated and delivered
under this Indenture; provided, however, that nothing contained in this Section
or elsewhere in this Indenture or in such Securities or in a Resolution of the
Company or Officers' Certificate or supplemental indenture is intended to or
shall limit execution by the Company or authentication and delivery by the
Trustee of Securities under the circumstances contemplated by Sections 2.5, 2.6,
2.7, 3.2, 3.3, 10.4 or upon surrender in part of any Securities for conversion
or exchange into Capital Stock of the Company or other securities pursuant to
its terms or pursuant to the terms of such Securities;

               (c)  The date or dates (if any) on which the principal of the
Securities of such series is payable;

               (d)  The rate or rates at which the Securities of such series
shall bear interest, if any, the rate or rates and extent to which Additional
Interest or other interest, if any, shall be payable, the date or dates from
which such interest shall accrue, the dates on which such interest shall be
payable, the record date for the interest payable on any interest payment date
and the right of the Company to defer or extend an interest payment date,
whether and under what circumstances Additional Tax Sums on such Securities
shall be payable, the notice, if any to holders of such Securities regarding the
determination of interest on a floating-rate Security and the manner of giving
such notice and the basis upon which interest shall be calculated if other than
that of a 360-day year of twelve 30-day months;

               (e)  The place or places where  Securities of such series may be
presented for payment and for the other purposes provided in Section 4.2;

                                        9

<PAGE>

               (f)  Any price or prices at which, any date or dates on which,
any period or periods within which, and any terms and conditions upon which
Securities of such series may be redeemed or prepaid, in whole or in part, at
the option of the Company;

               (g)  The type or types (if any) of Capital Stock of the Company
into which, any period or periods within which, and any terms and conditions
upon which Securities of such series may be made payable, converted, exchanged
in whole or in part, at the option of the holder or of the Company;

               (h)  If other than denominations of $1,000 and any whole multiple
thereof, the denominations in which Securities of such series shall be issuable;

               (i)  If other than the principal amount thereof, the portion of
the principal amount of Securities of such series which shall be payable upon
declaration of acceleration of the Maturity thereof pursuant to Section 6.1;

               (j)  If other than such coin or currency of the United States
of America as at the time of payment is legal tender for payment of public or
private debts, the coin or currency (which may be a composite currency) in which
payment of the principal of and interest, if any, on the Securities of such
series shall be payable;

               (k)  If the principal of or interest, if any, on the Securities
of such series are to be payable, at the election of the Company or a holder
thereof, in a coin or currency (including composite currency) other than that in
which the Securities of such series are stated to be payable, the date or dates
on which, the period or periods within which, the time and manner of determining
the exchange rate between the currency in which such Securities are to be paid
pursuant to such election and the terms and conditions upon which, such election
may be made;

               (l)  If the amounts of payments of principal of or interest, if
any, on the Securities of such series may be determined with reference to an
index based on a coin or currency (including composite currency) other than that
in which the Securities of such series are stated to be payable, the manner in
which such amounts shall be determined;

               (m)  If the Securities of such series are payable at Maturity
or upon earlier redemption in Capital Stock, the terms and conditions upon which
such payment shall be made;

               (n)  The Person or Persons who shall be registrar  for the
Securities of such series, and the place or places where the Register of
Securities of the series shall be kept;

               (o)  Any deletions from, modifications of or additions to the
Events of Default or covenants of the Company with respect to the Securities of
such series, whether or not such Events of Default or covenants are consistent
with the Events of Default or covenants set forth herein;

               (p)  Whether any Securities of such series are to be issuable
in global form with or without coupons, and, if so, the Depositary for such
global Securities, whether such Securities are to be issued in temporary or
permanent global form or both and whether beneficial owners of interests in any
such global Security may exchange such interests for definitive Securities of
such series and of like tenor of any authorized form and denomination and the
circumstances under which, and the place or places where, any such exchanges may
occur, if other than in the manner provided in Section 2.5;

               (q)  The form of the related Trust Agreement and Markel
Guarantee, if applicable;

               (r)  Whether any Securities of such series are subject to any
securities law or other restrictions on transfer; and any other terms of the
series (which terms shall not be inconsistent with the provisions of this
Indenture);

                                       10

<PAGE>

               (s)       Any right of the Company to (i) shorten or extend the
Maturity, or (ii) defer payments of interest;

or in any case, the method for determining such terms, the persons authorized to
determine such terms and the limits, if any, within which any such determination
of such terms is to be made.

         The Securities of all series shall be subordinate to Senior
Indebtedness of the Company as provided in Article Fourteen. The applicable
Resolution of the Company, Officers' Certificate or supplemental indenture may
provide that Securities of any particular series may be issued at various times,
with different dates on which the principal or any installment of principal is
payable, with different rates of interest, if any, or different methods by which
interest may be determined, with different dates from which such interest shall
accrue, with different dates on which such interest may be payable or with any
different terms other than Events of Default but all such Securities of a
particular series shall for all purposes under this Indenture including, but not
limited to, voting and Events of Default, be treated as Securities of a single
series.

         If any of the terms of any series of Securities are established by
action taken pursuant to a Resolution of the Company, a copy of an appropriate
record of such action shall be certified by the Corporate Secretary or an
Assistant Corporate Secretary of the Company and delivered to the Trustee at or
prior to the delivery of the Officers' Certificate or supplemental indenture
setting forth the terms of the series.

         At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities of any series executed by the
Company to the Trustee for authentication by it, and the Trustee shall thereupon
authenticate and deliver such Securities to or upon the written order of the
Company, signed by any two of the Chairman of the Board, the President, any Vice
President, the Treasurer, the Controller or the Corporate Secretary of the
Company or by any of the Chairman of the Board, President, any Vice President,
the Treasurer, the Controller or the Corporate Secretary of the Company and
either an Assistant Treasurer or an Assistant Corporate Secretary, without any
further corporate action by the Company. All Securities of any one series need
not be issued at the same time and, unless otherwise so provided by the Company,
a series may be reopened for issuances of additional Securities of such series
or to establish additional terms of such series of Securities. If the form or
terms of the Securities of the series have been established in or pursuant to a
Resolution of the Company and set forth in an Officers' Certificate, or set
forth in one or more supplemental indentures hereto, as permitted by this
Section and Section 2.2, in authenticating such Securities, and accepting the
additional responsibilities under this Indenture in relation to such Securities,
the Trustee shall be entitled to receive, and (subject to Section 7.1) shall be
fully protected in relying upon:

               (x)       an Opinion of Counsel to the effect that:

                    (i)  the form or forms and terms, or if all Securities
         of such series are not to be issued at one time, the manner of
         determining the terms of such Securities, have been established in
         conformity with the provisions of this Indenture;

                    (ii) all conditions precedent provided for in this
         Indenture to the authentication and delivery of such Securities
         have been complied with and that such Securities when completed by
         appropriate insertions, executed under the Company's corporate
         seal and attested by duly authorized officers of the Company,
         delivered by duly authorized officers of the Company to the
         Trustee for authentication pursuant to this Indenture, and
         authenticated and delivered by the Trustee and issued by the
         Company in the manner and subject to any conditions specified in
         such Opinion of Counsel, will constitute valid and binding
         obligations of the Company, enforceable against the Company in
         accordance with their terms, except as enforcement thereof may be
         subject to or limited by bankruptcy, insolvency, reorganization,
         moratorium, arrangement, fraudulent conveyance, fraudulent
         transfer or other similar laws relating to or affecting creditors'
         rights

                                       11

<PAGE>

         generally, and subject to general principles of equity (regardless
         of whether enforcement is sought in a proceeding in equity or at
         law); and

              (iii) if the Securities of such series have been registered
         under the Securities Act, that this Indenture has been qualified
         under the Trust Indenture Act;

and

              (y)    an Officers' Certificate stating that, to the best
knowledge of the Persons executing such certificate, no event which is, or after
notice or lapse of time would become, an Event of Default with respect to any of
the Securities shall have occurred and be continuing.

         The Trustee shall not be required to authenticate such Securities if
the issue of such Securities pursuant to this Indenture will affect the
Trustee's own rights, duties or immunities under the Securities and this
Indenture or otherwise in a manner which is not reasonably acceptable to the
Trustee or if the Trustee being advised by counsel, determines that such action
may not lawfully be taken.

         If all the Securities of any series are not to be issued at one time,
it shall not be necessary to deliver either an Opinion of Counsel or an
Officers' Certificate at the time of issuance of each Security, provided that
such Opinion of Counsel and Officers' Certificate, with appropriate
modifications, are instead delivered at or prior to the time of issuance of the
first Security of such series.

         Each Security shall be dated the date of its authentication.

         2.2  Form of Securities and Trustee's Certificate of Authenticity. The
Securities of each series shall be substantially of the tenor and terms as shall
be authorized in or pursuant to a Resolution of the Company and set forth in an
Officers' Certificate, or set forth in an indenture or indentures supplemental
hereto in each case with such appropriate insertions, omissions, substitutions
and other variations as are required or permitted by this Indenture, and may
have such letters, numbers or other marks of identification or designation and
such legends or endorsements thereon as the Company may deem appropriate and as
are not inconsistent with the provisions of this Indenture, or as may be
required to comply with any law or with any rule or regulation made pursuant
thereto or with any rule or regulation of any stock exchange or automated
quotation system on which the Securities may be listed, or to conform to usage.
If the form of Securities of any series is authorized by action taken pursuant
to a Resolution of the Company, a copy of an appropriate record of such action
shall be certified by the Corporate Secretary or an Assistant Corporate
Secretary of the Company and delivered to the Trustee at or prior to the
delivery of the Officers' Certificate contemplated by Section 2.1 setting forth
the terms of the series.

         The Securities may be printed, lithographed or fully or partly
engraved.

         The Trustee's certificate of authentication shall be in substantially
the following form:

         "This is one of the Securities, of the series designated herein,
referred to in the within-mentioned Indenture.

                  [Date]            THE CHASE MANHATTAN BANK, as Trustee


                                    By: ______________________________
                                              Authorized Officer"


         If Securities of a series are issuable in temporary or permanent global
form, as specified pursuant to Section 2.1, then, notwithstanding clause (h) of
Section 2.1 and the provisions of Section 2.3, such Security shall represent

                                       12

<PAGE>

such amount of the outstanding Securities of such series as shall be specified
therein and may provide that it shall represent the aggregate amount of
outstanding Securities of such series from time to time endorsed thereon and
that the aggregate amount of outstanding Securities of such series represented
thereby may from time to time be increased or reduced to reflect exchanges or
transfers (in any event, not to exceed the aggregate principal amount authorized
from time to time pursuant to Section 2.1). Any endorsement of a Security in
global form to reflect the amount, or any increase or decrease in the amount, of
outstanding Securities represented thereby shall be made by the Trustee in such
manner and upon instructions given by such person or persons as shall be
specified in such Security or by the Company. Subject to the provisions of
Section 2.4 and, if applicable, Section 2.6, the Trustee shall deliver and
redeliver any Security in global form in the manner and upon written
instructions given by the person or persons specified in such Security or by the
Company. Any instructions by the Company with respect to endorsement or delivery
or redelivery of a Security in global form after the original issuance of the
Securities of such series shall be in writing, and shall not be objected to in
writing by the Depositary, but need not comply with Section 15.4 and need not be
accompanied by an Opinion of Counsel.

         Unless otherwise specified pursuant to Section 2.1, payment of
principal of and any premium and any interest on any Security in global form
shall be made to the person or persons specified therein.

         The owners of beneficial interests in any global Security shall have no
rights under this Indenture with respect to any global Security held on their
behalf by a Depositary, and such Depositary may be treated by the Company, the
Trustee, and any agent of the Company or the Trustee as the sole holder and
owner of such global Security for all purposes whatsoever. Notwithstanding the
foregoing, nothing herein shall prevent the Company, the Trustee or any agent of
the Company or the Trustee from giving effect to any written certification,
proxy or other authorization furnished by a Depositary, or impair, as between a
Depositary and its participants in any global Security, the operation of
customary practices governing the exercise of the rights of a holder of a
Security of any series, including, without limitation, the granting of proxies
or other authorization of participants to give or take any request, demand,
authorization, direction, notice, consent, waiver or other action that a holder
is entitled to give or take under this Indenture.

         Neither the Company, the Trustee nor any Authenticating Agent will have
any responsibility or liability for any aspect of the records relating to or
payments made on account of beneficial ownership interests of a global Security
or for maintaining, supervising or reviewing any records relating to such
beneficial ownership interests.

         Each Depositary designated pursuant to Section 2.1 for a global
Security must, to the extent required by applicable law or regulation, be a
clearing agency registered under the Securities Exchange Act of 1934, as amended
(the "Exchange Act"), and any other applicable statute or regulation.

         2.3   Denominations of and Payment of Interest on Securities. The
Securities of each series shall be issuable as fully registered Securities
without coupons in such denominations as shall be specified as contemplated by
Section 2.1 (except as provided in Section 2.2 and Section 2.6). In the absence
of any such provisions with respect to the Securities of any series, the
Securities of such series shall be issuable in denominations of $1,000 and
integral multiples of $1,000 in excess thereof.

         If the Securities of any series shall bear interest, each Security of
such series shall bear interest from the applicable date at the rate or rates
per annum, and such interest shall be payable on the dates, specified on, or
determined in the manner provided in, the Security. The person in whose name any
Security is registered at the close of business on any record date (as defined
below) for the Security with respect to any interest payment date for such
Security shall be entitled to receive the interest payable thereon on such
interest payment date notwithstanding the cancellation of such Security upon any
registration of transfer, exchange or conversion thereof subsequent to such
record date and prior to such interest payment date, unless such Security shall
have been called for redemption on a date fixed for redemption subsequent to
such record date and prior to such interest payment date or unless the Company
shall default in the payment of interest due on such interest payment date on
such Security, in which case such defaulted interest shall be paid to the person
in whose name such Security (or any Security or Securities issued

                                       13

<PAGE>

upon registration of transfer or exchange thereof) is registered at the close of
business on the record date for the payment of such defaulted interest, or
except as otherwise specified as contemplated by Section 2.1. The term "record
date" as used in this Section with respect to any regular interest payment date
for any Security shall mean such day or days as shall be specified as
contemplated by Section 2.1; provided, however, that in the absence of any such
provisions with respect to any Security, such term shall mean: (1) if such
interest payment date is the first day of a calendar month, the fifteenth day of
the calendar month next preceding such interest payment date; or (2) if such
interest payment date is the fifteenth day of a calendar month, the first day of
such calendar month; provided, further, that (except as otherwise specified as
contemplated by Section 2.1) if the day which would be the record date as
provided herein is not a Business Day, then it shall mean the Business Day next
preceding such day. Such term, as used in this Section, with respect to the
payment of any defaulted interest on any Security shall mean (except as
otherwise specified as contemplated by Section 2.1) the fifth day next preceding
the date fixed by the Company for the payment of defaulted interest, established
by notice given by first class mail by or on behalf of the Company to the holder
of such Security not less than 10 days preceding such record date, or, if such
fifth day is not a Business Day, the Business Day next preceding such fifth day.

         2.4  Execution of Securities. The Securities shall be signed on behalf
of the Company, manually or in facsimile, by its Chairman of the Board,
President, any Vice President, Treasurer or under its corporate seal, which may
be affixed thereto or printed, engraved or otherwise reproduced thereon, by
facsimile or otherwise and attested by its Corporate Secretary or one of its
Assistant Corporate Secretaries of the Corporate Secretaries of the Company.
Only such Securities as shall bear thereon a certificate of authentication
substantially in the form recited herein, executed by or on behalf of the
Trustee manually by an authorized officer, shall be entitled to the benefits of
this Indenture or be valid or obligatory for any purpose. Such certificate of
authentication by the Trustee upon any Security executed by the Company shall be
conclusive evidence that the Security so authenticated has been duly
authenticated and delivered hereunder and that the holder is entitled to the
benefits of this Indenture. Typographical or other errors or defects in the seal
or facsimile signature on any Security or in the text thereof shall not affect
the validity or enforceability of such Security if it has been duly
authenticated and delivered by the Trustee.

         In case any officer of the Company who shall have signed any of the
Securities, manually or in facsimile, shall cease to be such officer before the
Securities so signed shall have been authenticated and delivered by the Trustee,
or disposed of by the Company, such Securities nevertheless may be authenticated
and delivered or disposed of as though the person who signed such Securities had
not ceased to be such officer of the Company; and any Security may be signed on
behalf of the Company, manually or in facsimile, by such persons as, at the
actual date of the execution of such Security, shall be the proper officers of
the Company, although at the date of the execution of this Indenture any such
person was not such officer.

         2.5  Registration, Transfer and Exchange of Securities. Securities of
any series (other than a global Security, except as set forth below) may be
exchanged for a like aggregate principal amount of Securities of the same series
of the same tenor and terms of other authorized denominations. Securities to be
exchanged shall be surrendered at the offices or agencies to be maintained by
the Company in accordance with the provisions of Section 4.2 and the Company
shall execute and the Trustee shall authenticate and deliver, or cause to be
authenticated and delivered, in exchange therefor the Security or Securities
which the Securityholder making the exchange shall be entitled to receive.

         The Company shall keep, at one of the offices or agencies to be
maintained by the Company in accordance with the provisions of Section 4.2 with
respect to the Securities of each series, a Register (the "Register") in which,
subject to such reasonable regulations as it may prescribe, the Company shall
register the Securities of such series and the transfer of Securities of such
series as in this Article provided. Such Register shall be in written form or in
any other form capable of being converted into written form within a reasonable
time. At all reasonable times the Register shall be open for inspection by the
Trustee and any registrar of the Securities of such series other than the
Trustee. Upon due presentment for registration of transfer of any Security of
any series at the offices or agencies of the Company to be maintained by the
Company in accordance with Section 4.2 with respect to the Securities of such
series, the Company shall execute and register and the Trustee shall
authenticate and deliver in the name of the

                                       14

<PAGE>

transferee or transferees a new Security or Securities of the same series of
like tenor and terms for a like aggregate principal amount of authorized
denominations.

         Every Security issued upon registration of transfer or exchange of
Securities pursuant to this Section shall be the valid obligation of the
Company, evidencing the same debt, and entitled to the same benefits under this
Indenture, as the Security or Securities surrendered upon registration of such
transfer or exchange.

         All Securities of any series presented or surrendered for exchange,
registration of transfer, redemption, conversion or payment shall, if so
required by the Company or any registrar of the Securities of such series, be
accompanied by a written instrument or instruments of transfer, in form
satisfactory to the Company and such registrar, duly executed by the registered
holder or by his attorney duly authorized in writing.

         No service charge shall be made for any exchange or registration of
transfer of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge and any other expense (including
fees and expenses of the Trustee) that may be imposed in relation thereto.

         The Company shall not be required to exchange or register the transfer
of (a) any Securities of any series during a period beginning at the opening of
business fifteen days before the day of selection for redemption of outstanding
Securities of such series and ending at the close of business on the relevant
redemption date, or (b) any Securities or portions thereof called or selected
for redemption, except, in the case of Securities called for redemption in part,
the portion thereof not so called for redemption.

         Notwithstanding any other provision of this Section, unless and until
it is exchanged in whole or in part for Securities in definitive form, a global
Security representing all or a portion of the Securities of a series may not be
transferred, except as a whole by the Depositary for such series to a nominee of
such Depositary or by a nominee of such Depositary to such Depositary or another
nominee of such Depositary or by such Depositary or any such nominee to a
successor Depositary for such series or a nominee of such successor Depositary.

         Notwithstanding the foregoing, except as otherwise specified pursuant
to Section 2.1, any global Security shall be exchangeable pursuant to this
Section only as provided in this paragraph. If at any time the Depositary for
the Securities of a series notifies the Company that it is unwilling or unable
to continue as Depositary for the Securities of such series, or if at any time
the Depositary for the Securities of such series shall cease to be a "clearing
agency" registered under the Exchange Act, the Company shall appoint a successor
Depositary with respect to the Securities of such series. If (a) a successor
Depositary for the Securities of such series is not appointed by the Company
within 90 days after the Company receives such notice or becomes aware of such
ineligibility (thereby automatically making the Company's election pursuant to
Section 2.1 no longer effective with respect to the Securities of such series),
(b) the beneficial owners of interests in a global Security are entitled to
exchange such interests for definitive Securities of such series and of the same
tenor and terms, as specified pursuant to Section 2.1, (c) there shall have
occurred and be continuing an Event of Default with respect to the Securities of
such series, or (d) the Company in its sole discretion determines that the
Securities of any series issued in the form of one or more global Securities
shall no longer be represented by such global Security or Securities, then
without unnecessary delay, but, if appropriate, in any event not later than the
earliest date on which such interest may be so exchanged, the Company shall
deliver to the Trustee definitive Securities in aggregate principal amount equal
to the principal amount of such global Security, executed by the Company and
authenticated by the Trustee. On or after the earliest date on which such
interests are or may be so exchanged, such global Security shall be surrendered
by the Depositary to the Trustee, as the Company's agent for such purpose, to be
exchanged, in whole or from time to time in part, for definitive Securities upon
payment by the beneficial owners of such interest, at the option of the Company,
of a service charge for such exchange and of a proportionate share of the cost
of printing such definitive Securities, and the Trustee shall authenticate and
deliver, (a) to each person specified by the Depositary in exchange for each
portion of such global Security, an equal aggregate principal amount of
definitive Securities of the same series of authorized denominations and of the
same tenor and terms as the portion of such global Security to be exchanged, and
(b) to such Depositary a global Security in a denomination equal to the
difference, if any, between

                                       15

<PAGE>

the principal amount of the surrendered global security and the aggregate
principal amount of definitive Securities delivered to holders thereof;
provided, however, that no such exchanges may occur during a period beginning at
the opening of business 15 days before any selection of Securities of that
series to be redeemed and ending on the relevant redemption date. If a Security
is issued in exchange for any portion of a global Security after the close of
business at the office or agency where such exchange occurs on (i) any record
date and before the opening of business at such office or agency on the relevant
interest payment date, or (ii) any record date for the payment of defaulted
interest and before the opening of business at such office or agency on the
related proposed date for payment of defaulted interest, then interest or
default interest, as the case may be, will not be payable on such interest
payment date or proposed date for payment of defaulted interest, as the case may
be, in respect of such Security, but will be payable on such interest payment
date or proposed date for payment of defaulted interest, as the case may be,
only to the person to whom interest in respect of such portion of such global
Security is payable in accordance with the provisions of this Indenture and such
global Security.

     2.6   Temporary Securities. Pending the preparation of definitive
Securities of any series, the Company may execute and the Trustee shall, upon
the written order of the Company, authenticate and deliver temporary Securities
of such series (printed, lithographed, mimeographed or otherwise produced) of
any denomination and substantially in the form of the definitive Securities of
such series, but with or without a recital of specific redemption prices or
conversion provisions and with such omissions, insertions and variations as may
be appropriate for temporary Securities, all as may be determined by the
Company. Temporary Securities may contain such reference to any provisions of
this Indenture as may be appropriate. Every such temporary Security shall be
authenticated by the Trustee upon the same conditions and in substantially the
same manner, and with the same effect, as the definitive Securities. Without
unreasonable delay the Company will execute and deliver to the Trustee
definitive Securities of such series and thereupon any or all temporary
Securities of such series may be surrendered in exchange therefor, at the
offices or agencies to be maintained by the Company as provided in Section 4.2
with respect to the Securities of such series, and the Trustee shall, upon the
written order of the Company, authenticate and deliver in exchange for such
temporary Securities an equal aggregate principal amount of definitive
Securities of such series. Until so exchanged, the temporary Securities of any
series shall in all respects be entitled to the same benefits under this
Indenture as definitive Securities of such series authenticated and delivered
hereunder.

     2.7   Mutilated, Destroyed, Lost or Stolen Securities. In case any
temporary or definitive Security shall become mutilated or be destroyed, lost or
stolen, the Company, in the case of any mutilated Security shall, and in the
case of any destroyed, lost or stolen Security in its discretion may, execute,
and upon its request the Trustee shall authenticate and deliver, or cause to be
authenticated and delivered, a new Security of the same series of like tenor and
terms in exchange and substitution for the mutilated Security, or in lieu of and
in substitution for the Security so destroyed, lost or stolen. In case any such
Security shall have matured or shall be about to mature, instead of issuing a
substituted Security, the Company may pay or authorize payment of the same
(without surrender thereof, except in the case of a mutilated Security). In
every case the applicant for a substituted Security or for such payment shall
furnish to the Company and the Trustee such security or indemnity as may be
required by them to save each of them harmless, and, in every case of
destruction, loss or theft, the applicant shall also furnish to the Company and
to the Trustee evidence to their satisfaction of the destruction, loss or theft
of such Security and of the ownership thereof. The Trustee may authenticate any
such substituted Security and deliver the same, or the Trustee or any Paying
Agent of the Company may make any such payment, upon the written request or
authorization of any officer of the Company. Upon the issue of any substituted
Security, the Company may require the payment of a sum sufficient to cover any
tax or other governmental charge that may be imposed in relation thereto and any
other reasonable expenses connected therewith (including the fees and expenses
of the Trustee).

     To the extent permitted by mandatory provisions of law, every substituted
Security issued pursuant to the provisions of this Section in substitution for
any destroyed, lost or stolen Security shall constitute an additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security shall be found at any time, and shall be entitled to all the
benefits of this Indenture equally and proportionately with any and all other
Securities of the same series duly issued hereunder.

                                       16

<PAGE>

     To the full extent legally enforceable, all Securities shall be held and
owned upon the express condition that the foregoing provisions are exclusive
with respect to the replacement or payment of mutilated, destroyed, lost or
stolen Securities and shall preclude any and all other rights or remedies
notwithstanding any law or statute now existing or hereafter enacted to the
contrary with respect to the replacement or payment of negotiable instruments or
other securities without their surrender.

     2.8   Cancellation and Destruction of Surrendered Securities. All
Securities surrendered for the purpose of payment, redemption, exchange,
substitution or registration of transfer, shall, if surrendered to the Company
or any agent of the Company or of the Trustee, be delivered to the Trustee, and
the same, together with Securities surrendered to the Trustee for cancellation,
shall be canceled by it, and no Securities shall be issued in lieu thereof
except as expressly permitted by any of the provisions of this Indenture. The
Trustee shall dispose of canceled Securities in accordance with its customary
procedures and deliver a certificate of disposition thereof to the Company
unless by an Officers' Certificate, the Company shall direct that canceled
Securities be returned to it. If the Company shall purchase or otherwise acquire
any of the Securities, however, such purchase or acquisition shall not operate
as a payment, redemption or satisfaction of the indebtedness represented by such
Securities unless and until the Company, at its option, shall deliver or
surrender the same to the Trustee for cancellation.

     2.9   Authenticating Agents. The Trustee may from time to time appoint one
or more Authenticating Agents with respect to one or more series of Securities,
which shall be authorized to act on behalf of the Trustee and subject to its
direction in authenticating and delivering Securities of such series pursuant
hereto in connection with exchanges, registrations of transfer, redemptions or
conversions, as fully to all intents and purposes as though any such
Authenticating Agent had been expressly authorized to authenticate and deliver
Securities of such series, and Securities so authenticated shall be entitled to
the benefits of this Indenture and shall be valid and obligatory for all
purposes as though authenticated by the Trustee. Wherever reference is made in
this Indenture to the authentication or delivery of Securities by the Trustee or
the Trustee's certificate of authentication, such reference shall be deemed to
include authentication or delivery on behalf of the Trustee by an Authenticating
Agent and a certificate of authentication executed on behalf of the Trustee by
an Authenticating Agent. Each Authenticating Agent shall at all times be a
corporation (including a banking association) organized and doing business under
the laws of the United States or any State or territory thereof or of the
District of Columbia, having a combined capital and surplus of at least five
million dollars ($5,000,000) authorized under such laws to exercise corporate
trust powers and subject to supervision or examination by federal, state,
territorial, or District of Columbia authorities. If such corporation publishes
reports of condition at least annually, pursuant to law or to the requirements
of the aforesaid supervising or examining authority, then for the purposes of
this Section, the combined capital and surplus of such corporation shall be
deemed to be its combined capital and surplus as set forth in its most recent
report of condition so published. If at any time an Authenticating Agent shall
cease to be eligible in accordance with the provisions of this Section, it shall
resign immediately in the manner and with the effect herein specified in this
Section.

     Any corporation succeeding to the corporate agency business of an
Authenticating Agent shall continue to be an Authenticating Agent, if such
successor corporation is otherwise eligible under this Section, without the
execution or filing of any paper or any further act on the part of the Trustee
or the Authenticating Agent or such successor corporation.

     Any Authenticating Agent may at any time resign by giving written notice of
resignation to the Trustee and to the Company. The Trustee may at any time
terminate the agency of an Authenticating Agent by giving written notice of
termination to such Authenticating Agent and to the Company. Upon receiving such
a notice of resignation or upon such a termination, or in case at any time an
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section, the Trustee may appoint a successor Authenticating
Agent. Any successor Authenticating Agent upon acceptance of its appointment
hereunder shall become vested with all the rights, powers and duties of its
predecessor hereunder, with like effect as if originally named as an
Authenticating Agent herein. No successor Authenticating Agent shall be
appointed unless eligible under the provisions of this Section.

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<PAGE>

     The Company agrees to pay to each Authenticating Agent from time to time
reasonable compensation for its services under this Section.

     Any Authenticating Agent by the acceptance of its appointment shall be
deemed to have agreed with the Trustee that: it will perform and carry out the
duties of an Authenticating Agent as herein set forth, including among other
things the duties to authenticate and deliver Securities of any series for which
it has been appointed an Authenticating Agent when presented to it in connection
with exchanges, registrations of transfer or any redemptions or conversions
thereof; it will furnish from time to time as requested by the Trustee
appropriate records of all transactions carried out by it as Authenticating
Agent and will furnish the Trustee such other information and reports as the
Trustee may reasonably require; it is eligible for appointment as Authenticating
Agent under this Section and will notify the Trustee promptly if it shall cease
to be so qualified; and it will indemnify the Trustee against any loss,
liability or expense incurred by the Trustee and will defend any claim asserted
against the Trustee by reason of any acts or failures to act of the
Authenticating Agent but it shall have no liability for any action taken by it
at the specific written direction of the Trustee.

     2.10   Deferrals of Interest Payment Dates. If specified as contemplated by
Section 2.1 or Section 2.2 with respect to the Securities of a particular
series, so long as no Event of Default has occurred and is continuing, the
Company shall have the right, at any time during the term of such series, from
time to time to defer the payment of interest on such Securities for such period
or periods as may be specified as contemplated by Section 2.1 (each, an
"Extension Period") during which Extension Periods the Company shall have the
right to make partial payments of interest on any interest payment date. No
Extension Period shall end on a date other than an interest payment date or
extend beyond the Stated Maturity. At the end of any such Extension Period the
Company shall pay all interest then accrued and unpaid on the Securities
(together with Additional Interest or other interest thereon, if any, at the
rate specified for the Securities of such series to the extent permitted by
applicable law).

     2.11   Right of Set-Off. With respect to the Securities of a series issued
to a Markel Capital Trust, notwithstanding anything to the contrary in this
Indenture (but subject to the last paragraph of Section 6.5), the Company shall
have the right to set off any payment it is otherwise required to make
thereunder in respect of any such Security to the extent the Company has
theretofore made, or is concurrently on the date of such payment making, such
payment under the Markel Guarantee relating to such Security or under Section
6.5 of this Indenture.

     2.12   Shortening or Extension of Stated Maturity. If specified as
contemplated by Section 2.1 or Section 2.2 with respect to the Securities of a
particular series, the Company shall have the right to (i) shorten the Stated
Maturity of the principal of the Securities of such series at any time to any
date not earlier than the first date on which the Company has the right, if any,
to redeem the Securities of such series, and (ii) extend the Stated Maturity of
the principal of the Securities of such series at any time at its election for
one or more periods, but in no event to a date later than the 49th anniversary
of the first interest payment date following the Original Issue Date of the
Securities of such series; provided that, if the Company elects to exercise its
right to extend the Stated Maturity of the principal of the Securities of such
series pursuant to this clause (ii), at the time such election is made and at
the time of extension (A) the Company is not in bankruptcy, otherwise insolvent
or in liquidation, (B) the Company is not in default in the payment of any
interest or principal on such Securities, (C) in the case of any series of
Securities issued to a Markel Capital Trust, such Markel Capital Trust is not in
arrears on payments of Distributions on the Preferred Securities issued by such
Markel Capital Trust and no deferred Distributions are accumulated, and (D) such
Securities are rated not less than BBB- by Standard & Poor's Ratings Services or
Baa3 by Moody's Investors Service, Inc. or the equivalent by any other
nationally recognized statistical rating organization. In the event the Company
elects to shorten or extend the Stated Maturity of the Securities of a
particular series, it shall give notice to the Trustee (not less than 45 days
prior to the effectiveness thereof), and the Trustee shall give notice of such
shortening or extension to the holders not less than 30 nor more than 60 days
prior to the effectiveness thereof.

     2.13   Agreed Tax Treatment. Each Security issued hereunder shall provide
that the Company and, by its acceptance of a Security or a beneficial interest
therein, the holder of, and any Person that acquires a beneficial

                                       18

<PAGE>

interest in, such Security agree that for United States federal, state and local
tax purposes it is intended that such Security constitute indebtedness.

     2.14   CUSIP Numbers. The Company in issuing the Securities may use "CUSIP"
numbers (if then generally in use), and, if so, the Trustee shall use "CUSIP"
numbers in notices of redemption as a convenience to holders of Securities;
provided that any such notice may state that no representation is made as to the
correctness of such numbers either as printed on the Securities or as contained
in any notice of a redemption and that reliance may be placed only on the other
identification numbers printed on the Securities, and any such redemption shall
not be affected by any defect in or omission of such numbers. The Company will
promptly notify the Trustee of any change in the CUSIP numbers.

                                   ARTICLE III
                            REDEMPTION OF SECURITIES

     3.1    Applicability of Article. Securities of any series which are
redeemable prior to Stated Maturity shall be redeemable in accordance with their
terms and (except as otherwise specified as contemplated by Section 2.1 for
Securities of any series) in accordance with this Article.

     3.2    Mailing of Notice of Redemption. In case the Company shall desire to
exercise any right to redeem all or, as the case may be, any part of the
Securities of any series pursuant to this Indenture, it shall give notice of
such redemption to holders of the Securities to be redeemed as hereinafter in
this Section provided.

     The Company covenants that it will pay to the Trustee or one or more Paying
Agents (or if the Company is acting as its own Paying Agent, segregate and hold
in trust as provided in Section 4.4), on the date of such redemption, an amount
of money in the applicable currency sufficient to redeem on the redemption date
all the Securities so called for redemption at the applicable redemption price,
together with any accrued interest or any Additional Tax Sums on the Securities
to be redeemed to but excluding the date fixed for redemption.

     Notice of redemption shall be given to the holders of Securities to be
redeemed as a whole or in part by mailing by first class mail, postage prepaid,
a notice of such redemption not less than 20 nor more than 60 days prior to the
date fixed for redemption, unless a shorter time is specified in the Securities
to be redeemed, to their last addresses as they shall appear upon the Register,
but failure to give such notice by mailing in the manner herein provided to the
holder of any Security designated for redemption as a whole or in part, or any
defect therein, shall not affect the validity of the proceedings for the
redemption of any other Security.

     Any notice which is mailed in the manner herein provided shall be
conclusively presumed to have been duly given, whether or not the holder
receives the notice.

     Each such notice of redemption shall identify the Securities to be redeemed
(including CUSIP numbers) and specify the date fixed for redemption and the
redemption price at which Securities are to be redeemed (or if the redemption
price cannot be calculated prior to the time the notice is required to be given,
the manner of calculation thereof), and shall state that payment of the
redemption price of the Securities or portions thereof to be redeemed will be
made at any of the offices or agencies to be maintained by the Company in
accordance with the provisions of Section 4.2 with respect to the Securities to
be redeemed, upon presentation and surrender of such Securities or portions
thereof, and that, if applicable, interest accrued to the date fixed for
redemption will be paid as specified in said notice and on and after said date
interest thereon will cease to accrue and shall also specify, if applicable, the
conversion price and the date on which the right to convert the Securities will
expire and that holders must comply with the terms of the Securities in order to
convert their Securities. If less than all the Securities of any series are to
be redeemed, the notice of redemption to each holder shall specify such holder's
Securities of such series to be redeemed as a whole or in part. In case any
Security is to be redeemed in part only, the notice which relates to such
Security shall state the portion of the principal amount thereof to be redeemed
(which shall be equal to an authorized

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<PAGE>

denomination for Securities of such series), and shall state that on and after
the redemption date, upon surrender of such Security, the holder will receive
the redemption price in respect to the principal amount thereof called for
redemption and, without charge, a new Security or Securities of the same series
of authorized denominations for the principal amount thereof remaining
unredeemed.

     In the case of any redemption at the election of the Company, the Company
shall, at least 60 days prior to the date fixed for redemption (unless a shorter
notice shall be satisfactory to the Trustee), notify the Trustee of such
redemption date, the basis for such redemption and of the principal amount of
Securities of the applicable series to be redeemed. In the case of any
redemption of Securities prior to the expiration of any restriction on such
redemption provided in the terms of such Securities or that is subject to
compliance with conditions provided in the terms of such Securities, the Company
shall furnish the Trustee with an Officers' Certificate evidencing compliance
with such restriction or conditions. If less than all the Securities of such
series are to be redeemed, thereupon the Trustee shall select, by lot, or in any
manner it shall deem fair, the Securities of such series to be redeemed as a
whole or in part and shall thereafter promptly notify the Company in writing of
the particular Securities of such series or portions thereof to be redeemed. If
the Securities of any series to be redeemed consist of Securities having
different dates on which the principal or any installment of principal is
payable or different rates of interest, if any, or different methods by which
interest may be determined or have any other different tenor or terms, then the
Company may, by written notice to the Trustee, direct that Securities of such
series to be redeemed shall be selected from among groups of such Securities
having specified tenor or terms and the Trustee shall thereafter select the
particular Securities to be redeemed in the manner set forth in the preceding
sentence from among the group of such Securities so specified.

     3.3    When Securities Called for Redemption Become Due and Payable. If the
giving of notice of redemption shall have been completed as above provided, the
Securities or portions of Securities specified in such notice shall become due
and payable on the date and at the place or places stated in such notice at the
applicable redemption price, together, if applicable, with any interest accrued
(including any Additional Interest or other interest) to but excluding the date
fixed for redemption, and on and after such date fixed for redemption (unless
the Company shall default in the payment of such Securities at the applicable
redemption price, together with any interest accrued to the date fixed for
redemption) any interest on the Securities or portions of Securities so called
for redemption shall cease to accrue, and, except as provided in Sections 7.5
and 12.4, such Securities shall cease from and after the date fixed for
redemption to be entitled to any benefit or security under this Indenture, and
the holders thereof shall have no right in respect of such Securities except the
right to receive the redemption price thereof and any unpaid interest accrued to
but excluding the date fixed for redemption. On presentation and surrender of
such Securities at said place of payment in said notice specified, such
Securities or portions thereof shall be paid and redeemed by the Company at the
applicable redemption price, together with any interest accrued to but excluding
the date fixed for redemption; provided, however, that, except as otherwise
specified as contemplated by Section 2.1, any regular payment of interest
becoming due on the date fixed for redemption shall be payable to the holders of
the Securities registered as such on the relevant record date as provided in
Article Two hereof. Upon surrender of any Security which is redeemed in part
only, the Company shall execute and the Trustee shall authenticate and deliver
at the expense of the Company a new Security of the same series of like tenor
and terms of authorized denomination in principal amount equal to the unredeemed
portion of the Security so surrendered; except that if a global Security is so
surrendered, the Company shall execute, and the Trustee shall authenticate and
deliver to the Depositary for such global Security, without service charge, a
global Security in a denomination equal to and in exchange for the unredeemed
portion of the principal of the global Security so surrendered.

     If any Security called for redemption shall not be so paid upon surrender
thereof for redemption, the principal shall, until paid, bear interest from the
date fixed for redemption at the rate borne by or prescribed therefor in the
Security, or, in the case of a Security which does not bear interest, at the
rate of interest set forth therefor in the Security to the extent permitted by
law.

                                   ARTICLE IV

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<PAGE>

                       PARTICULAR COVENANTS OF THE COMPANY

     The Company covenants as follows:

     4.1   Payment of Principal of and Interest on Securities. The Company will
duly and punctually pay or cause to be paid the principal of and interest
(including any Additional Interest and/or Additional Tax Sums due thereon), if
any, on each of the Securities at the time and places and in the manner provided
herein and in the Securities. Except as otherwise specified as contemplated by
Section 2.1, if the Securities of any series bear interest, each installment of
interest on the Securities of such series may at the option of the Company be
paid (i) by mailing a check or checks for such interest payable to the Person
entitled thereto pursuant to Section 2.3 to the address of such person as it
appears on the Register of the Securities of such series or (ii) by transfer to
an account maintained by the Person entitled thereto as specified in the
Register of Securities, provided that proper transfer instructions have been
received by the record date.

     4.2   Maintenance of Offices or Agencies for Registration of Transfer,
Exchange and Payment of Securities. So long as any of the Securities shall
remain outstanding, the Company will maintain an office or agency where the
Securities may be presented for registration, conversion, exchange and
registration of transfer as in this Indenture provided, and where notices and
demands to or upon the Company in respect of the Securities or of this Indenture
may be served, and where the Securities may be presented for payment. In case
the Company shall designate and maintain some office or agency other than the
previously designated office or agency, it shall give the Trustee prompt written
notice thereof. In case the Company shall fail to maintain any such office or
agency or shall fail to give such notice of the location or of any change in the
location thereof to the Trustee, presentations and demands may be made and
notices may be served at the principal office of the Trustee.

     In addition to such office or agency, the Company may from time to time
constitute and appoint one or more other offices or agencies for such purposes
with respect to Securities of any series, and one or more paying agents for the
payment of Securities of any series, in such cities or in one or more other
cities, and may from time to time rescind such appointments, as the Company may
deem desirable or expedient, and as to which the Company has notified the
Trustee.

     4.3   Appointment to Fill a Vacancy in the Office of Trustee. The Company,
whenever necessary to avoid or fill a vacancy in the office of Trustee, will
appoint, in the manner provided in Section 7.10, a Trustee, so that there shall
at all times be a Trustee with respect to each series of Securities hereunder.

     4.4   Duties of Paying Agent.

           (a)      If the Company shall appoint a Paying Agent other than the
Trustee with respect to Securities of any series, it will cause such Paying
Agent to execute and deliver to the Trustee an instrument in which such Paying
Agent shall agree with the Trustee, subject to the provisions of this Section
and Section 12.3,

           (i)      that it will hold all sums held by it as such agent for
     the payment of the principal of or interest, if any, on the Securities
     of such series (whether such sums have been paid to it by the Company
     or by any other obligor on the Securities of such series) in trust for
     the benefit of the holders of the Securities of such series entitled
     to such principal or interest and will notify the Trustee of the
     receipt of sums to be so held,

           (ii)     that it will give the Trustee notice of any failure by
     the Company (or by any other obligor on the Securities of such series)
     to make any payment of the principal of or interest on the Securities
     of such series when the same shall be due and payable, and

           (iii)    that it will at any time during the continuance of any
     Event of Default, upon the written request of the Trustee, deliver to
     the Trustee all sums so held in trust by it.

                                       21

<PAGE>

           (b)   Whenever the Company shall have one or more Paying Agents with
respect to the Securities of any series, it will, prior to each due date of the
principal of or any interest on a Security of such series, deposit with a Paying
Agent of such series a sum sufficient to pay the principal or interest so
becoming due, such sum to be held in trust for the benefit of the holders of
Securities of such series entitled to such principal or interest, and (unless
such Paying Agent is the Trustee) the Company will promptly notify the Trustee
of its action or failure so to act.

           (c)   If the Company shall act as its own Paying Agent with respect
to the Securities of any series, it will, on or before each due date of the
principal of or any interest on a Security of such series, set aside, segregate
and hold in trust for the benefit of the holder of such Security, a sum
sufficient to pay such principal or interest so becoming due and will notify the
Trustee of such action, or any failure by it or any other obligor on the
Securities of such series to take such action and will at any time during the
continuance of any Event of Default, upon the written request of the Trustee,
deliver to the Trustee all sums so held in trust by it.

           (d)   Anything in this Section to the contrary notwithstanding, the
Company may, at any time, for the purpose of obtaining a satisfaction and
discharge of this Indenture with respect to one or more or all series of
Securities hereunder, or for any other reason, pay or cause to be paid to the
Trustee all sums held in trust for such series by it, or any Paying Agent
hereunder, as required by this Section, such sums are to be held by the Trustee
upon the trust herein contained; and upon such payment by any Paying Agent to
the Trustee, such Paying Agent shall be released from all further liability with
respect to such sums.

           (e)   Anything in this Section to the contrary notwithstanding, the
agreement to hold sums in trust as provided in this Section is subject to the
provisions of Sections 12.3 and 12.4.

      4.5  Officers' Certificate as to Defaults; Notices of Certain. The Company
will, so long as any of the Securities are outstanding, deliver to the Trustee
no later than 120 days after the end of each calendar year, beginning with the
year 200_, a certificate signed by the Company's principal executive officer,
principal financial officer or principal accounting officer stating that a
review has been made under his or her supervision of the activities of the
Company during such year and of the performance under this Indenture and, to the
best of his or her knowledge, the Company has complied with all conditions and
covenants under this Indenture throughout such calendar year, or if there has
been a default in the fulfillment of any such obligation, specifying each such
default known and the nature and status thereof. For purposes of this Section,
such compliance shall be determined without regard to any period of grace or
requirement of notice provided under this Indenture. In addition, the Company
shall give the notice to the Trustee as and when required by the fourth
paragraph of Section 14.1.

      4.6  Waiver of Covenants. The Company may omit in any particular instance
to comply with any covenant or condition specifically contained in this
Indenture for the benefit of one or more series of Securities, if before the
time for such compliance the holders of a majority in principal amount of the
Securities of all series affected (all series voting as one class) at the time
outstanding (determined as provided in Section 8.4) shall waive such compliance
in such instance, but no such waiver shall extend to or affect such covenant or
condition except to the extent so expressly waived, and, until such waiver shall
become effective, the obligations of the Company and the duties of the Trustee
in respect of any such covenant or condition shall remain in full force and
effect.

      4.7  Additional Tax Sums. In the case of the Securities of a series issued
to a Markel Capital Trust, so long as no Event of Default has occurred and is
continuing and except as otherwise specified as contemplated by Section 2.1 or
Section 2.2, in the event that (i) a Markel Capital Trust is the holder of all
of the Outstanding Securities of such series, (ii) a Tax Event in respect of
such Markel Capital Trust shall have occurred and be continuing and (iii) the
Company shall not have (a) redeemed the Securities of such series or (b)
terminated such Markel Capital Trust pursuant to the termination provisions of
the related Trust Agreement, the Company shall pay to such Markel Capital Trust
(and any permitted successor or assign under the related Trust Agreement) for so
long as such Markel Capital Trust (or its permitted successor or assignee) is
the registered holder of any Securities of such series, such additional amounts
as may be necessary in order that the amount of Distributions then due and

                                       22

<PAGE>

payable by such Markel Capital Trust on the related Preferred Securities and
Common Securities that at any time remain outstanding in accordance with the
terms thereof shall not be reduced as a result of any additional taxes, duties
and other governmental charges to which such Markel Capital Trust has become
subject as a result of such Tax Event (but not including withholding taxes
imposed on holders of such Preferred Securities and Common Securities) (the
"Additional Tax Sums"). Whenever in this Indenture or the Securities there is a
reference in any context to the payment of principal of or interest on the
Securities, such reference shall be deemed to include payment of the Additional
Tax Sums provided for in this paragraph to the extent that, in such context,
Additional Tax Sums are, were or would be payable in respect thereof pursuant to
the provisions of this Section and express reference to the payment of
Additional Tax Sums (if applicable) in any provisions hereof shall not be
construed as excluding Additional Tax Sums in those provisions hereof where such
express reference is not made; provided, however, that the deferral of the
payment of interest pursuant to Section 2.10 or the Securities shall not defer
the payment of any Additional Tax Sums that may be then due and payable.

     4.8   Additional Covenants. The Company covenants and agrees with each
holder of Securities of a series issued to a Markel Capital Trust that it shall
not (i) declare or pay any dividends or distributions on, or redeem, purchase,
acquire, or make a liquidation payment with respect to, any shares of the
Company's Capital Stock (which includes Common Stock and preferred stock), or
(ii) make any payment of principal of or interest or premium, if any, on or
repay, repurchase or redeem any debt securities of the Company that rank on a
parity with or junior to the Securities of such series or make any guarantee
payments with respect to any Markel Guarantee or other guarantee by the Company
of debt securities of any Subsidiary that by its terms ranks on a parity with or
junior to the Securities of such series (other than (a) dividends or
distributions in Common Stock, or options, warrants or rights to subscribe for
or purchase shares of Common Stock of the Company; (b) any declaration of a
dividend in connection with the implementation of a Rights Plan, or the issuance
of any Capital Stock of any class or series of preferred stock of the Company
under any Rights Plan in the future or the redemption or repurchase of any
rights distributed pursuant to a Rights Plan; (c) payments under any Markel
Guarantee relating to the Preferred Securities issued by the Markel Capital
Trust holding the Securities of such series; (d) as a result of reclassification
of the Company's Capital Stock or the exchange or conversion of one class or
series of the Company's Capital Stock pursuant to the conversion or exchange
provisions of such Capital Stock or the security being converted or exchanged
and (f) purchases of Common Stock related to the issuance of Common Stock or
rights under any of the Company's stock option, stock purchase, stock loan or
other benefit plans for its directors, officers, employees, consultants or
advisors or any of the Company's dividend reinvestment plans, in each case as
now existing or hereafter established or amended) if at such time (i) there
shall have occurred any event of which the Company has actual knowledge that (a)
with the giving of notice or the lapse of time or both, would constitute an
Event of Default hereunder and (b) in respect of which the Company shall not
have taken reasonable steps to cure, (ii) the Company shall be in default with
respect to its payment of any obligations under the related Markel Guarantee or
(iii) the Company shall have given notice of its election to begin an Extension
Period as provided in Section 2.10 and shall not have rescinded such notice, or
such Extension Period, or any extension thereof, shall be continuing.

     The Company also covenants with each holder of Securities of a series
issued to a Markel Capital Trust (i) to maintain directly or indirectly 100%
ownership of the Common Securities of such Markel Capital Trust; provided,
however, that any permitted successor or assignee of the Company hereunder may
succeed to the Company's ownership of such Common Securities, (ii) not to
voluntarily terminate, wind up or liquidate such Markel Capital Trust, except
(a) in connection with a prepayment in full of the Securities or a distribution
of the Securities of such series to the holders of Preferred Securities in
liquidation of such Markel Capital Trust or (b) in connection with certain
mergers, consolidations or amalgamations permitted by the relevant Trust
Agreement and (iii) to use its reasonable efforts, consistent with the terms and
provisions of such Trust Agreement, to cause such Markel Capital Trust to remain
classified as a grantor trust and not an association taxable as a corporation
for United States federal income tax purposes.

     4.9   Calculation of Original Issue Discount. The Company shall file with
the Trustee promptly at the end of each calendar year (i) a written notice
specifying the amount of original issue discount (including daily rates and
accrual periods) accrued on outstanding Securities as of the end of such year
and (ii) such other specific

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<PAGE>

information relating to such original issue discount as may then be relevant
under the Internal Revenue Code of 1986, as amended from time to time.



                                    ARTICLE V
                SECURITYHOLDERS' LISTS AND REPORTS BY THE COMPANY
                                 AND THE TRUSTEE

     5.1   Company to Furnish Trustee Information as to the Names and Addresses
of Securityholders. The Company covenants and agrees that it will furnish or
cause to be furnished to the Trustee, semiannually not more than 5 days after
each record date for payment of interest, and at such other times as the Trustee
may request in writing within 30 days after receipt by the Company of any such
request, a list in such form as the Trustee may reasonably require containing
all information in the possession or control of the Company, or any Paying Agent
or any registrar of the Securities of each series, other than the Trustee, as to
the names and addresses of the holders of Securities of such series obtained (in
the case of each list other than the first list) since the date as of which the
next previous list was furnished; provided, however, that if the Trustee shall
be the registrar of the Securities of such series, no such list need be
furnished; and provided further that the Company shall not be obligated to
provide such a list of Securityholders at any time the list of Securityholders
does not differ from the most recent list of Securityholders given to the
Trustee by the Company. Any such list may be dated as of a date not more than
fifteen days prior to the time such information is furnished or caused to be
furnished, and need not include information received after such date.

     5.2   Trustee to Preserve Information as to the Names and Addresses of
Securityholders Received by It.

     The Trustee shall comply with the obligations imposed upon it pursuant to
Section 312 of the Trust Indenture Act.

     Each and every holder of Securities, by receiving and holding the same,
agrees with the Company and the Trustee that neither the Company nor the Trustee
nor any Paying Agent nor any registrar shall be held accountable by reason of
the disclosure of any information as to the names and addresses of the holders
of Securities in accordance with Section 312(b) of the Trust Indenture Act,
regardless of the source from which such information was derived, and that the
Trustee shall not be held accountable by reason of mailing any material pursuant
to a request made under Section 312(b) of the Trust Indenture Act.

     5.3   Annual and Other Reports to be Filed by Company with Trustee.

           (a)   The Company covenants and agrees to file with the Trustee
within fifteen days after the Company is required to file the same with the
Commission, copies of the annual reports and of the information, documents and
other reports (or copies of such portions of any of the foregoing as the
Commission may from time to time by rules and regulations prescribe) which the
Company may be required to file with the Commission pursuant to Section 13 or
Section 15(d) of the Exchange Act; or, if the Company is not required to file
information, documents or reports pursuant to either of such Sections, then it
will file with the Trustee and the Commission, in accordance with rules and
regulations prescribed from time to time by the Commission, such of the
supplementary and periodic information, documents and reports which may be
required pursuant to Section 13 of the Exchange Act in respect of a security
listed and registered on a national securities exchange as may be prescribed
from time to time in such rules and regulations.

           (b)   The Company covenants and agrees to file with the Trustee and
the Commission, in accordance with the rules and regulations prescribed from
time to time by the Commission, such additional

                                       24

<PAGE>

information, documents, and reports with respect to compliance by the Company
with the conditions and covenants provided for in this Indenture as may be
required from time to time by such rules and regulations.

           (c)   The Company covenants and agrees to transmit to the holders of
Securities within 30 days after the filing thereof with the Trustee, in the
manner and to the extent provided in subsection (c) of Section 5.4 with respect
to reports pursuant to subsection (a) of said Section 5.4, such summaries of any
information, documents and reports required to be filed by the Company pursuant
to subsections (a) and (b) of this Section as may be required by rules and
regulations prescribed from time to time by the Commission.

           (d)   Delivery of such reports, information and documents to the
Trustee is for informational purposes only and the Trustee's receipt of such
shall not constitute constructive notice of any information contained therein or
determinable from information contained therein, including the Company's
compliance with any of its covenants hereunder (as to which the Trustee is
entitled to rely exclusively on Officers' Certificates).

     5.4   Trustee to Transmit Annual Report to Securityholders.

           (a)   Within 60 days after May 15, 200_, and on or before May 15 in
every year thereafter, if and so long as any Securities are outstanding
hereunder, the Trustee shall transmit to the Securityholders as hereinafter in
this Section provided, a brief report dated as of the preceding May 15 with
respect to any of the events specified in Section 313(a) of the Trust Indenture
Act which may have occurred within the previous twelve (12) months (but if no
such event has occurred within such period no report need be transmitted):

           (b)   The Trustee shall transmit to the Securityholders, as
hereinafter provided, a brief report with respect to the character and amount of
any advances (and if the Trustee elects so to state, the circumstances
surrounding the making thereof) made by the Trustee (as such) since the date of
the last report transmitted pursuant to the provisions of subsection (a) of this
Section (or if such report has not yet been so transmitted, since the date of
execution of this Indenture), for the reimbursement of which it claims or may
claim a lien or charge prior to that of the Securities of any series on property
or funds held or collected by it as Trustee, and which it has not previously
reported pursuant to this subsection, except that the Trustee shall not be
required (but may elect) to report such advances if such advances so remaining
unpaid aggregate not more than 10 percent of the principal amount of Securities
of all series outstanding as of the date of such report, such report to be
transmitted within 90 days after such time.

           (c)   Reports pursuant to this Section shall be transmitted by mail
to all holders of Securities of any series, as the names and addresses of such
holders shall appear upon the Register of the Securities of such series.

           (d)   A copy of each such report shall, at the time of such
transmission to Securityholders, be filed by the Trustee with each stock
exchange upon which the Securities of any series are listed and also with the
Commission. The Company will promptly notify the Trustee when and as the
Securities of any series become listed on any stock exchange.



                                   ARTICLE VI
                 REMEDIES OF THE TRUSTEE AND SECURITYHOLDERS ON
                                EVENT OF DEFAULT

     6.1   Events of Default Defined. The term "Event of Default" whenever used
herein with respect to Securities of any series shall mean any one of the
following events:

           (a)   default in the payment of any installment of interest upon, or
any Additional Tax Sums payable in respect of any interest on, any of the
Securities of such series as and when the same shall become due and

                                       25

<PAGE>

payable, and continuance of such default for a period of 60 days (subject to the
deferral of any due date in the case of an Extension Period); or

          (b) default in the payment of all or any part of the principal of or
any Additional Tax Sums payable in respect of the principal on any of the
Securities of such series as and when the same shall become due and payable
whether upon Maturity, upon any redemption, by declaration or otherwise; or

          (c) failure on the part of the Company duly to observe or perform in
any covenants or agreements (other than covenants to pay interest, principal and
premium, which are subject to subsections (a) and (b) above of this Section) on
the part of the Company in the Securities or in this Indenture (including any
supplemental indenture or pursuant to any Officers' Certificate as contemplated
by Section 2.1) which are for the benefit of the Securities of such series, for
a period of 90 days after there has been given, by registered or certified mail,
to the Company by the Trustee, or to the Company and the Trustee by the holders
of not less than 33% in principal amount of the Securities of such series and
all other series so benefited (all series voting as one class) at the time
outstanding under this Indenture a written notice specifying such failure and
stating that such notice is a "Notice of Default" hereunder, unless the Trustee,
or the Trustee and the Holders of a principal amount of Securities of such
series not less than the principal amount of Securities the Holders of which
gave such notice, as the case may be, shall agree in writing to an extension of
such period prior to its expiration; provided, however, that the Trustee or the
Trustee and the Holders of such principal amount of Securities of such series,
as the case may be, shall be deemed to have agreed to an extension of such
period if corrective action is initiated by the Company within such period and
is being diligently pursued; or

          (d) the commencement by the Company of a voluntary case under Chapter
7 or Chapter 11 of the federal Bankruptcy Code or any other similar state or
federal law now or hereafter in effect, or the consent by the Company to the
entry of a decree or order for relief in an involuntary case under any such law,
or the consent by the Company to the appointment of or the taking possession by
a liquidating agent or committee, conservator or receiver for the Company or any
substantial part of its property, or the general assignment by the Company for
the benefit of its creditors, or the admission by the Company in writing of its
inability to pay its debts as they become due; or

          (e) the entry of a decree or order for relief by a court having
jurisdiction in the premises in respect of the Company in an involuntary case
under Chapter 7 or Chapter 11 of the federal Bankruptcy Code or any other
similar state or federal law now or hereafter in effect, and the continuance of
any such decree or order unstayed and in effect for a period of 90 days, or the
appointment of or the taking possession by a liquidating agent or committee,
conservator or receiver for the Company or any substantial part of its property,
and the continuance of any such appointment unstayed and in effect for a period
of 90 days.

     If an Event of Default shall have occurred and be continuing, either the
Trustee or the holders of not less than 33% in principal amount of all the then
outstanding Securities of the series as to which such Event of Default has
occurred, by notice in writing to the Company (and to the Trustee if given by
Securityholders), may declare the principal amount (or if Securities of any
series are Original Issue Discount Securities, such portion of the principal
amount as may be specified in the terms of such series) of all the Securities of
such series, together with any accrued interest, to be due and payable
immediately, and upon any such declaration the same shall become and shall be
immediately due and payable; provided, however, that in the case of the
Securities of a series issued to a Markel Capital Trust, if upon an Event of
Default, the Trustee or the holders of at least 33% in principal amount of the
outstanding Securities of such series fail to declare the principal of all the
Securities of that series to be immediately due and payable, the holders of at
least 33% in aggregate liquidation amount of the corresponding series of
Preferred Securities then outstanding shall have such right by a notice in
writing to the Company and the Trustee.

     The foregoing provisions, however, are subject to the condition that if, at
any time after the principal amount (or specified portion thereof) of the
Securities of any one or more series (or of all the Securities, as the case may
be) shall have been so declared due and payable, and before any judgment or
decree for the payment of moneys

                                       26

<PAGE>

due shall have been obtained or entered as hereinafter provided, the Company
shall pay or shall deposit with the Trustee a sum sufficient to pay all matured
installments of interest upon all the Securities of such series (or upon all the
Securities, as the case may be) and the principal of any and all Securities of
such series (or of any and all the Securities, as the case may be) which shall
have become due otherwise than by declaration (with interest on overdue
installments of interest to the extent permitted by law and on such principal at
the rate or rates of interest borne by, or prescribed therefor in, the
Securities of each such series to the date of such payment or deposit) and the
amounts payable to the Trustee under Section 7.6, and any and all defaults under
the Indenture with respect to Securities of such series (or all Securities, as
the case may be), other than the nonpayment of principal of and any accrued
interest on Securities of such series (or any Securities, as the case may be)
which shall have become due by declaration, shall have been cured, remedied or
waived as provided in Section 6.6, then and in every such case the holders of a
majority in principal amount of the Securities of such series (or of all the
Securities, as the case may be) then outstanding and as to which such Event of
Default has occurred (such series or all series voting as one class, if more
than one series are so entitled) by written notice to the Company and to the
Trustee, may rescind and annul such declaration and its consequences. In the
case of Securities issued to a Markel Capital Trust, should the holders of such
Securities fail to annul such declaration and waive such default, the holders of
a majority in aggregate liquidation amount of related Preferred Securities shall
have such right; but no such rescission and annulment shall extend to or shall
affect any subsequent default, or shall impair any right consequent thereon.

     In case the Trustee, any holder of Securities or any holder of Preferred
Securities shall have proceeded to enforce any right under this Indenture and
such proceedings shall have been discontinued or abandoned because of such
rescission or annulment or for any other reason or shall have been determined
adversely to the Trustee, such holder of Securities or such holder of Preferred
Securities then and in every such case the Company, the Trustee, the holders of
the Securities of such series (or of all the Securities, as the case may be) and
the holders of Preferred Securities shall be restored respectively to their
former positions and rights hereunder, and all rights, remedies and powers of
the Company and the Trustee, the holders of the Securities of such series (or of
all the Securities, as the case may be) and the holders of Preferred Securities
shall continue as though no such proceedings had been taken.

     6.2 Covenant of Company to Pay to Trustee Whole Amount Due on Securities on
Default in Payment of Interest or Principal. The Company covenants that (1) in
case default shall be made in the payment of any installment of interest on any
of the Securities of any series as and when the same shall become due and
payable, and such default shall have continued for a period of 30 days (subject
to the deferral of any due date in the case of an Extension Period), or (2) in
case default shall be made in the payment of all or any part of the principal of
any of the Securities of any series as and when the same shall become due and
payable, whether upon Maturity, upon any redemption, by declaration or
otherwise, then, upon demand of the Trustee, the Company will pay to the
Trustee, for the benefit of the holders of the Securities of such series, the
whole amount that then shall have become due and payable on all such Securities
of such series for principal or interest, or both, as the case may be, with
interest upon the overdue principal and installments of interest (to the extent
permitted by law) at the rate or rates of interest borne by or prescribed
therefor in the Securities of such series; and, in addition thereto, such
further amount as shall be sufficient to cover the costs and expenses of
collection, including reasonable compensation to the Trustee, its agents and
counsel, and any expenses or disbursements reasonably incurred, and all
reasonable advances made hereunder by the Trustee, its agents, attorneys and
counsel, except as a result of its negligence or bad faith.

     In case the Company shall fail forthwith to pay such amounts upon such
demand, the Trustee, in its own name and as trustee of an express trust, shall
be entitled and empowered to institute any actions or proceedings at law or in
equity for the collection of the sums so due and unpaid, and may prosecute any
such action or proceeding to judgment or final decree, and may enforce any such
judgment or final decree against the Company or any other obligor upon such
Securities, and collect in the manner provided by law out of the property of the
Company or any other obligor upon such Securities wherever situated the moneys
adjudged or decreed to be payable.

     The Trustee shall be entitled and empowered, either in its own name or as
trustee of an express trust, or as attorney-in-fact for the holders of the
Securities of any series, or in any one or more of such capacities (irrespective
of whether the principal of the Securities of such series shall then be due and
payable, whether upon Maturity, upon

                                       27

<PAGE>

any redemption, by declaration or otherwise, and irrespective of whether the
Trustee shall have made any demand pursuant to the provisions of this Section)
to file and prove a claim or claims for the whole amount of principal (or, if
the Securities of such series are Original Issue Discount Securities, such
portion of the principal amount as may be specified in the terms of such series)
and interest owing and unpaid in respect of the Securities of such series and to
file such other documents as may be necessary or advisable in order to have the
claims of the Trustee (including any claim for reasonable compensation of the
Trustee, its agents and counsel, and for reimbursement of all expenses and
disbursements reasonably incurred, and all reasonable advances made hereunder by
the Trustee, its agents and counsel, except as a result of its negligence or bad
faith) and of the holders of the Securities of such series allowed in any equity
receivership, insolvency, bankruptcy, liquidation, arrangement, readjustment,
reorganization or any other judicial proceedings relative to the Company or any
other obligor on the Securities of such series or their creditors, or their
property. The Trustee is hereby irrevocably appointed (and the successive
respective holders of the Securities of each series by taking and holding the
same shall be conclusively deemed to have so appointed the Trustee) the true and
lawful attorney-in-fact of the respective holders of the Securities of such
series, with authority to make and file in the respective names of the holders
of the Securities of such series, or on behalf of the holders of the Securities
of such series as a class, any proof of debt, amendment of proof of debt, claim,
petition or other document in any such proceeding and to receive payment of any
sums becoming distributable on account thereof, and to execute any such other
papers and documents and to do and perform any and all such acts and things for
and on behalf of such holders of the Securities of such series, as may be
necessary or advisable in the opinion of the Trustee in order to have the
respective claims of the Trustee and of the holders of the Securities of such
series allowed in any such proceeding, and to receive payment of or on account
of such claims and to distribute the same, and any receiver, assignee, trustee,
liquidator, sequestrator or other similar official in any such judicial
proceeding is hereby authorized by each holder to make such payments to the
Trustee and, in the event that the Trustee shall consent to the making of such
payments directly to the holders, to pay to the Trustee any amount due to it
under Section 7.6; provided, however, that nothing herein shall be deemed to
authorize the Trustee to authorize or consent to or vote for or accept or adopt
on behalf of any Securityholder any plan of reorganization, arrangement,
adjustment or composition affecting the Securities of such series or the rights
of any holder thereof, or to authorize the Trustee to vote in respect of the
claim of any holder of Securities of such series in any such proceeding.

     All rights of action and of asserting claims under this Indenture, or under
any of the Securities of any series, may be enforced by the Trustee without the
possession of any of the Securities of such series, or the production thereof on
any trial or other proceeding relative thereto, and any such suit or proceeding
instituted by the Trustee, shall be brought in its own name as trustee of an
express trust, and any recovery of judgment shall be, after provision for the
payment of the reasonable compensation, expenses, disbursements and advances of
such Trustee, its agents and counsel, for the ratable benefit of the holders of
the Securities of such series.

     6.3  Application of Moneys Collected by Trustee. Any moneys collected by
the Trustee pursuant to Section 6.2 shall be applied in the order following, at
the date or dates fixed by the Trustee for the distribution of such moneys, upon
presentation of the several Securities in respect of which moneys have been
collected, and stamping thereon the payment, if only partially paid, and upon
surrender thereof if fully paid:

     First: To the payment of all amounts payable to the Trustee under Section
     7.6;

     Second: In case the principal of the outstanding Securities in respect of
     which moneys have been collected shall not have become due and be unpaid,
     to the payment of any unpaid interest on such Securities, in the order of
     the maturity of the installments of such interest, with interest upon the
     overdue installments of interest (so far as permitted by law and to the
     extent that such interest has been collected by the Trustee) at the rate or
     rates of interest borne by, or prescribed therefor in, such Securities,
     such payments to be made ratably to the persons entitled thereto, without
     discrimination or preference;

     Third: In case the principal of the outstanding Securities in respect of
     which such moneys have been collected shall have become due and be unpaid,
     whether upon Maturity, upon any redemption, by declaration or otherwise, to
     the payment of the whole amount then owing and unpaid upon such Securities

                                       28

<PAGE>

     for principal and interest, if any, with interest on the overdue principal
     and any installments of interest (so far as permitted by law and to the
     extent that such interest has been collected by the Trustee) at the rate or
     rates of interest borne by, or prescribed therefor in, such Securities; and
     in case such moneys shall be insufficient to pay in full the whole amount
     so due and unpaid upon such Securities, then to the payment of such
     principal and interest, without preference or priority of principal over
     interest, or of interest over principal, or of any installment of interest
     over any other installment of interest, or of any Security over any other
     Security, ratably to the aggregate of such unpaid principal and interest;
     and

     Fourth: To the payment of the remainder, if any, to the Company, its
     successors or assigns, or to whomsoever may be lawfully entitled to receive
     the same, or as a court of competent jurisdiction may direct.

     6.4     Limitation on Suits by Holders of Securities. No holder of any
Security of any series shall have any right by virtue or by availing of any
provision of this Indenture to institute any suit, action or proceeding in
equity or at law upon or under or with respect to this Indenture or for the
appointment of a receiver or trustee, or for any other remedy hereunder, unless
such holder previously shall have given to the Trustee written notice of an
Event of Default and of the continuance thereof, as hereinbefore provided, and
unless also the holders of not less than a majority in principal amount of all
the Securities at the time outstanding (considered as one class) shall have made
written request upon the Trustee to institute such action, suit or proceeding in
its own name as Trustee hereunder and shall have offered to the Trustee such
reasonable indemnity as it may require against the costs, expenses and
liabilities to be incurred therein or thereby, and the Trustee, for 60 days
after its receipt of such notice, request and offer of indemnity, shall have
neglected or refused to institute any such action, suit or proceeding and no
direction inconsistent with such written request shall have been given to the
Trustee pursuant to Section 6.6; it being understood and intended, and being
expressly covenanted by the taker and holder of every Security with every other
taker and holder and the Trustee, that no one or more holders of Securities
shall have any right in any manner whatever by virtue or by availing of any
provision of this Indenture to affect, disturb or prejudice the rights of the
holders of any other of such Securities, or to obtain or seek to obtain priority
over or preference to any other such holder, or to enforce any right under this
Indenture, except in the manner herein provided and for the equal, ratable and
common benefit of all holders of Securities. For the protection and enforcement
of the provisions of this Section, each and every Securityholder and the Trustee
shall be entitled to such relief as can be given either at law or in equity.

     Notwithstanding any other provisions in this Indenture, the right of any
holder of any Security to receive payment of the principal of and interest on
such Security, on or after the respective due dates expressed in such Security
(or, in the case of redemption on or after the date fixed for redemption), or to
institute suit for the enforcement of any such payment on or after such
respective dates, shall not be impaired or affected without the consent of such
holder.

     6.5     On Default Trustee May Take Appropriate Action; Direct Action. In
case of an Event of Default hereunder the Trustee may in its discretion proceed
to protect and enforce the rights vested in it by this Indenture by such
appropriate judicial proceedings as the Trustee shall deem most effectual to
protect and enforce any of such rights, either by suit in equity or by action at
law or by proceeding in bankruptcy or otherwise, whether for the specific
enforcement of any covenant or agreement contained in this Indenture or in aid
of the exercise of any power granted in this Indenture, or to enforce any other
legal or equitable right vested in the Trustee by this Indenture or by law.
Except as provided in the last paragraph of Section 2.7, all powers and remedies
given by this Article to the Trustee or to the Securityholders shall, to the
extent permitted by law, be deemed cumulative and not exclusive of any thereof
or of any other powers and remedies available to the Trustee or the holders of
the Securities, by judicial proceedings or otherwise, to enforce the performance
or observance of the covenants and agreements contained in this Indenture, and
no delay or omission of the Trustee, of any holder of any of the Securities or
any holder of Preferred Securities to exercise any right or power accruing upon
any Event of Default occurring and continuing as aforesaid shall impair any such
right or power, or shall be construed to be a waiver of any such default or an
acquiescence therein; and, subject to the provisions of Section 8.4, every power
and remedy

                                       29

<PAGE>

given by this Article or by law to the Trustee, to the Securityholders or the
holders of Preferred Securities may be exercised from time to time, and as often
as shall be deemed expedient, by the Trustee, by the Securityholders or by the
holders of Preferred Securities, as the case may be.

     In the case of Securities of a series issued to a Markel Capital Trust, any
holder of the corresponding series of Preferred Securities issued by such Markel
Capital Trust shall have the right, upon the occurrence of an Event of Default
described in Section 6.1(a) or (b) above, to institute a suit directly against
the Company (a "Direct Action") for enforcement of payment to such holder of
principal of (including premium, if any) and interest (including any Additional
Interest) on the Securities having a principal amount equal to the aggregate
liquidation amount of such Preferred Securities of the corresponding series held
by such holder. Notwithstanding any payments made to a holder of such Preferred
Securities by the Company pursuant to a Direct Action initiated by such holder,
the Company shall remain obligated to pay the principal of or interest due on
the Securities, and the Company shall be subrogated to the rights of the holder
of such Preferred Securities with respect to payments on the Preferred
Securities to the extent of any payments made by the Company to such holder in
any Direct Action.

     6.6 Rights of Holders of Majority in Principal Amount of Securities to
Direct Trustee and to Waive Default. The holders of at least a majority in
principal amount of the Securities of any one or more series or of all the
Securities, as the case may be (voting as one class), at the time outstanding
(determined as provided in Section 8.4) shall have the right to direct the time,
method, and place of conducting any proceeding for any remedy available to the
Trustee, or exercising any trust or power conferred on the Trustee under this
Indenture with respect to such one or more series; provided, however, that
subject to Section 7.1, the Trustee shall have the right to decline to follow
any such direction if the Trustee being advised by Opinion of Counsel determines
that the action so directed may not lawfully be taken, or if the Trustee in good
faith shall, by a Responsible Officer or Officers of the Trustee, determine that
the proceedings so directed would be illegal or involve it in personal liability
or be unduly prejudicial to the rights of Securityholders of such one or more
series not parties to such direction, and provided further that nothing in this
Indenture shall impair the right of the Trustee to take any action deemed proper
by the Trustee and which is not inconsistent with such direction by such
Securityholders of such one or more series. The holders of at least a majority
in principal amount of the Securities of all series as to which an Event of
Default hereunder has occurred (all series voting as one class) at the time
outstanding (determined as provided in Section 8.4) and, in the case of any
Preferred Securities of a series issued to a Markel Capital Trust, the holders
of at least a majority in aggregate liquidation amount of the Preferred
Securities issued by such Markel Capital Trust, may waive any past default
hereunder with respect to such series and its consequences, except a default in
the payment of the principal of or interest on any of such Securities or
Preferred Securities or in respect of a covenant or provision hereof which under
Article Ten cannot be modified or amended without the consent of the holder of
each Security so affected. Upon any such waiver, such default shall cease to
exist and any Event of Default arising therefrom shall be deemed to have been
cured for every purpose of this Indenture, but no such waiver shall extend to
any subsequent or other default or impair any right consequent thereon. Any such
waiver shall be deemed to be on behalf of the holders of all the Securities of
such series or, in the case of a waiver by holders of Preferred Securities
issued by such Markel Capital Trust, on behalf of all holders of Preferred
Securities issued by such Markel Capital Trust.

     6.7 Trustee to Give Notice of Defaults Known to It, but May Withhold in
Certain Circumstances. The Trustee shall, give to the holders of the Securities
of any such series notice of any default hereunder with respect to the
Securities of such series as and to the extent provided by the Trust Indenture
Act, actually known to the Trustee unless such default shall have been cured,
remedied or waived before the giving of such notice provided, however, that in
the case of any default of the character specified in Section 6.1(c), no such
notice to holders shall be given until at least 30 days after the occurrence
thereof; provided further, however, that, except in the case of default in the
payment of the principal of or interest on any of the Securities of such series,
the Trustee shall be protected in withholding such notice if and so long as the
Board of Directors, the Executive Committee, or a Trust Committee of directors
and/or Responsible Officers of the Trustee in good faith determines that the
withholding of such notice is in the interest of the holders of the Securities
of such series.

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     6.8 Requirement of an Undertaking to Pay Costs in Certain Suits Under the
Indenture or Against the Trustee. All parties to this Indenture agree, and each
holder of any Security by his acceptance thereof shall be deemed to have agreed,
that any court may in its discretion require, in any suit for the enforcement of
any right or remedy under this Indenture, or in any suit against the Trustee for
any action taken or omitted by it as Trustee, the filing by any party litigant
in such suit of an undertaking to pay the costs of such suit, and that such
court may in its discretion assess reasonable costs, including reasonable
attorneys' fees and expenses, against any party litigant in such suit, having
due regard to the merits and good faith of the claims or defenses made by such
party litigant; but the provisions of this Section shall not apply to any suit
instituted by the Trustee, to any suit instituted by any holder of Securities of
any series, or group of such Securityholders, holding in the aggregate more than
10 percent in principal amount of all the Securities (all series considered as
one class) outstanding, or to any suit instituted by any Securityholder for the
enforcement of the payment of the principal of or interest on any Security, on
or after the due date expressed in such Security (or in the case of any
redemption, on or after the date fixed for redemption).

                                   ARTICLE VII
                             CONCERNING THE TRUSTEE

     7.1 Upon Event of Default Occurring and Continuing, Trustee Shall Exercise
Powers Vested in It, and Use Same Degree of Care and Skill in Their Exercise, as
a Prudent Man Would Use. The Trustee, prior to the occurrence of an Event of
Default and after the curing, remedying or waiving of all Events of Default
which may have occurred, undertakes to perform such duties and only such duties
as are specifically set forth in this Indenture. In case an Event of Default has
occurred (which has not been cured, remedied or waived) the Trustee shall
exercise such of the rights and powers vested in it by this Indenture, and use
the same degree of care and skill in their exercise, as a prudent man would
exercise or use under the circumstances in the conduct of his own affairs.

     No provision of this Indenture shall be construed to relieve the Trustee
from liability for its own negligent action, its own negligent failure to act,
or its own willful misconduct; provided, however, that

         (a)  Prior to the occurrence of an Event of Default and after the
curing, remedying or waiving of all Events of Default which may have occurred:

         (i)  the duties and obligations of the Trustee shall be determined
     solely by the express provisions of this Indenture and the Trustee
     shall not be liable except for the performance of such duties and
     obligations as are specifically set forth in this Indenture, and no
     implied covenants or obligations shall be read into this Indenture
     against the Trustee; and

         (ii) in the absence of bad faith on the part of the Trustee, the
     Trustee may conclusively rely, as to the truth of the statements and
     the correctness of the opinions expressed therein, upon any
     certificates or opinions furnished to the Trustee and conforming to
     the requirements of this Indenture; but in the case of any such
     certificates or opinions which by any provision hereof are
     specifically required to be furnished to the Trustee, the Trustee
     shall be under a duty to examine the same to determine whether or not
     they conform to the requirements of this Indenture;

         (b)  The Trustee shall not be liable for any error of judgment made in
good faith by a Responsible Officer or Officers of the Trustee, unless it shall
be proved that the Trustee was negligent in ascertaining the pertinent facts
upon which such judgment was made;

         (c)  The Trustee shall not be liable with respect to any action taken
or omitted to be taken by it in good faith in accordance with the direction of
the holders of Securities pursuant to Section 6.6 relating to the time, method
and place of conducting any proceeding for any remedy available to the Trustee,
or exercising any trust or power conferred upon the Trustee, under this
Indenture;

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<PAGE>

         (d) Whether or not therein expressly so provided, every provision of
this Indenture relating to the conduct or affecting the liability of or
affording protection to the Trustee shall be subject to the provisions of this
Section 7.1; and

         (e) None of the provisions contained in this Indenture shall require
the Trustee to expend or risk its own funds or otherwise incur any financial
liability in the performance of any of its duties hereunder or in the exercise
of any of its rights or powers, if there is reasonable ground for believing that
the repayment of such funds or adequate indemnity against such risk or liability
is not reasonably assured to it.

     7.2 Reliance on Documents, Opinions, Etc.  Except as otherwise provided in
Section 7.1:

         (a) The Trustee may rely and shall be fully protected in acting or
refraining from acting in good faith upon any resolution, certificate,
statement, instrument, opinion, report, notice, request, direction, consent,
order, appraisal, bond, debenture, note, other evidence of indebtedness or other
paper or document reasonably believed by it to be genuine and to have been
signed, sent or presented by the proper party or parties;

         (b) Any request, direction, order or demand of the Company mentioned
herein shall be sufficiently evidenced by an Officers' Certificate (unless other
evidence in respect thereof be herein specifically prescribed); and any
Resolution of the Company may be evidenced to the Trustee by a copy thereof;

         (c) The Trustee may consult with counsel of its selection and the
advice of such counsel or any Opinion of Counsel with respect to legal matters
shall be full and complete authorization and protection in respect of any action
taken, suffered or omitted to be taken by it hereunder in good faith and in
accordance with such advice or Opinion of Counsel;

         (d) The Trustee shall be under no obligation to exercise any of the
rights or powers vested in it by this Indenture at the request or direction of
any of the Securityholders pursuant to this Indenture, unless such
Securityholders shall have offered to the Trustee such adequate security or
indemnity against the costs, expenses (including attorneys' fees and expenses)
and liabilities that might be incurred by it in complying with such request or
direction;

         (e) The Trustee shall not be liable for any action taken or omitted to
be taken by it in good faith and believed by it to be authorized or within the
discretion or rights or powers conferred upon it by this Indenture;

         (f) The Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, approval, bond,
debenture, note, other evidence of indebtedness or other paper or document,
unless requested in writing to do so by the holders of Securities pursuant to
Section 6.6, but the Trustee may make such further inquiry or investigation into
such facts or matters as it may see fit; provided, however, that if the payment
within a reasonable time to the Trustee of the costs, expenses or liabilities
likely to be incurred by it in the making of such investigation is, in the
opinion of the Trustee, not reasonably assured to the Trustee by the security
afforded to it by the terms of this Indenture, the Trustee may require adequate
indemnity against such costs, expenses or liabilities as a condition to so
proceeding; and provided further, that nothing in this subsection (f) shall
require the Trustee to give the Securityholders any notice other than that
required by Section 6.7. The reasonable expense of every such examination shall
be paid by the Company or, if paid by the Trustee, shall be repaid by the
Company upon demand;

         (g) The Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents or
attorneys and the Trustee shall not be responsible for any misconduct or
negligence on the part of any agent or attorney appointed by it hereunder;
provided, however, that the Trustee shall be responsible for its own negligence
or recklessness with respect to the selection of any such agent or attorney;

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<PAGE>

         (h) The Trustee shall be under no responsibility for the approval by it
in good faith of any expert for any of the purposes expressed in this Indenture;
and

         (i) The Trustee shall not be deemed to have notice of any Event of
Default unless a Responsible Officer of the Trustee in its Corporate Trust
Office has actual knowledge thereof or unless written notice of any event which
is in fact such a default is received by the Trustee at the Corporate Trust
Office of the Trustee from the Company or any Security holder, and such notice
references the Securities and this Indenture.

     7.3 Trustee Not Liable for Recitals in Indenture or in Securities. The
recitals contained herein and in the Securities (other than the certificate of
authentication on the Securities) shall be taken as the statements of the
Company, and the Trustee does not assume any responsibility for their
correctness. The Trustee makes no representations as to the validity or
sufficiency of this Indenture or of the Securities. The Trustee shall not be
accountable for the use or application by the Company of the proceeds of the
Securities of any series.

     7.4 May Hold Securities. The Trustee or any agent of the Trustee, in its
individual or any other capacity, may become the owner or pledgee of Securities
and, subject to Section 7.8, with the same rights it would have if it were not
Trustee or such agent.

     7.5 Moneys Received by Trustee to be Held in Trust without Interest.
Subject to the provisions of Section 12.4, all moneys received by the Trustee
shall, until used or applied as herein provided, be held in trust for the
purposes for which they were received, but need not be segregated from other
funds except to the extent required by law. The Trustee shall be under no
liability for interest on any moneys received by it hereunder.

     7.6 Trustee Entitled to Compensation, Reimbursement and Indemnity. The
Company covenants and agrees to pay to the Trustee from time to time, and the
Trustee shall be entitled to, such compensation as shall be agreed to in writing
between the Company and the Trustee (which shall not be limited by any provision
of law in regard to the compensation of a trustee of any express trust), and,
the Company will pay or reimburse the Trustee upon its request for all
reasonable expenses, disbursements and advances incurred or made by the Trustee
in connection with the acceptance or administration of its trust under this
Indenture (including the reasonable compensation and the reasonable expenses and
disbursements of its agents and counsel and of all persons not regularly in its
employ) except any such expense, disbursement or advance as may arise from its
negligence or bad faith. The Company also covenants and agrees to indemnify each
of the Trustee, any predecessor Trustee and their agents for, and to hold them
harmless against, any loss, liability or expense incurred without negligence or
bad faith on their part and arising out of or in connection with the acceptance
or administration of this trust and performance of their duties hereunder,
including the reasonable costs and expenses (including reasonable fees and
disbursements of their counsel) of defending themselves against any claim or
liability in connection with the exercise or performance of any of the powers or
duties hereunder. The obligations of the Company under this Section to
compensate the Trustee, to pay or reimburse the Trustee for expenses,
disbursements and advances and to indemnify and hold harmless the Trustee shall
constitute additional indebtedness hereunder and shall survive the satisfaction
and discharge of this Indenture and the resignation or removal of the Trustee.
Such additional indebtedness shall be secured by a lien prior to that of the
Securities upon all property and funds held or collected by the Trustee as such,
except funds held in trust for the payment of principal of or interest, if any,
on particular Securities.

     Without prejudice to any other rights available to the Trustee under
applicable law, when the Trustee incurs expenses or renders services in
connection with an Event of Default specified in Section 6.1(d) or Section
6.1(e), the expenses (including the reasonable charges and expenses of its
counsel) and the compensation for the services are intended to constitute
expenses of administration under any applicable federal or state bankruptcy,
insolvency or other similar law.

     7.7 Right of Trustee to Rely on Officers' Certificate where No Other
Evidence Specifically Prescribed. Except as otherwise provided in Section 7.1,
whenever in the administration of this Indenture the Trustee shall deem it
necessary or desirable that a matter be proved or established prior to taking,
suffering or

                                       33

<PAGE>

omitting to take any action hereunder, the Trustee (unless other evidence in
respect thereof be herein specifically prescribed) may, in the absence of
negligence or bad faith on its part, request and rely upon an Officers'
Certificate which, upon receipt of such request, shall be promptly delivered by
the Company.

     7.8  Disqualification; Conflicting Interests. If the Trustee has or shall
acquire any conflicting interest, within the meaning of the Trust Indenture Act,
the Trustee shall either eliminate such interest or resign, to the extent and in
the manner provided by, and subject to the provisions of, the Trust Indenture
Act and this Indenture.

     7.9  Requirements for Eligibility of Trustee. There shall at all times be a
Trustee hereunder that is a corporation, organized and doing business under the
laws of the United States of America, any state thereof or the District of
Columbia, eligible under Sections 310(a)(1) and (5) of the Trust Indenture Act
to act as trustee under an indenture qualified under the Trust Indenture Act and
that has a combined capital and surplus (computed in accordance with Section
310(a)(2) of the Trust Indenture Act) of at least $50,000,000 subject to
supervision or examination by federal or state authority. If at any time the
Trustee shall cease to be eligible in accordance with the provisions of this
Section, it shall resign immediately in the manner and with the effect
hereinafter specified in this Article.

     7.10 Resignation and Removal of Trustee.

          (a)  The Trustee, or any trustee or trustees hereafter appointed, may
at any time resign with respect to one or more or all series of Securities by
giving written notice of such resignation to the Company and by giving to the
holders of Securities of the applicable series notice thereof in the manner and
to the extent provided in subsection (c) of Section 5.4 with respect to reports
pursuant to subsection (a) of Section 5.4. Upon receiving such notice of
resignation and if the Company shall deem it appropriate evidence satisfactory
to it of such mailing, the Company shall promptly appoint a successor Trustee
with respect to the applicable series (it being understood that any successor
Trustee may be appointed with respect to the Securities of one or more or all of
such series and at any time there shall be only one Trustee with respect to the
Securities of any particular series) by written instrument, in duplicate,
executed pursuant to a Resolution of the Company, one copy of which instrument
shall be delivered to the resigning Trustee and one copy to the successor
Trustee. If no successor Trustee shall have been so appointed with respect to
any series and have accepted appointment within 30 days after the mailing of
such notice of resignation, the resigning Trustee may petition any court of
competent jurisdiction for the appointment of a successor Trustee, or any
Securityholder who has been a bona fide holder of a Security or Securities of
the applicable series for at least six months may, subject to the provisions of
Section 6.8, on behalf of himself and all others similarly situated, petition
any such court for the appointment of a successor Trustee. Such court may
thereupon after such notice, if any, as it may deem proper and prescribe,
appoint a successor Trustee.

          (b)  In case at any time any of the following shall occur:

               (i)   The Trustee shall fail to comply with Section 7.8
     after written request therefor by the Company or by any Securityholder
     who has been a bona fide holder of a Security or Securities of the
     applicable series for at least six months, or

               (ii)  The Trustee shall cease to be eligible in accordance
     with the provisions of Section 7.9 and shall fail to resign after
     written request therefor by the Company or by any such Securityholder,
     or

               (iii) The Trustee shall become incapable of acting, or shall
     be adjudged a bankrupt or insolvent, or a receiver of the Trustee or
     of its property shall be appointed, or any public officer shall take
     charge or control of the Trustee or of its property or affairs for the
     purpose of rehabilitation, conservation or liquidation,

                                       34

<PAGE>

then, in any such case, the Company may remove the Trustee with respect to the
applicable series and appoint a successor Trustee with respect to the applicable
series by written instrument, in duplicate, executed pursuant to a Resolution of
the Company, one copy of which instrument shall be delivered to the Trustee so
removed and one copy to the successor Trustee, or, subject to the provisions of
Section 6.8, any Securityholder who has been a bona fide holder of a Security or
Securities of the applicable series for at least six months may, on behalf of
himself and all others similarly situated, petition any court of competent
jurisdiction for the removal of the Trustee and the appointment of a successor
Trustee with respect to the applicable series. Such court may thereupon, after
such notice, if any, as it may deem proper and prescribe, remove the Trustee and
appoint a successor Trustee.

          (c) The holders of a majority in principal amount of the Securities of
any one series voting as a separate class or all series voting as one class at
the time outstanding (determined as provided in Section 8.4) may at any time
remove the Trustee with respect to the applicable series or all series, as the
case may be, and appoint a successor Trustee with respect to the applicable
series or all series, as the case may be, by written instrument or instruments
signed by such holders or their attorneys-in-fact duly authorized, or by the
affidavits of the permanent chairman and permanent secretary of a meeting of the
Securityholders (as elected in accordance with Section 9.5) evidencing the vote
upon a resolution or resolutions submitted thereto with respect to such removal
and appointment (as provided in Article Nine), and by delivery thereof to the
Trustee so removed, to the successor Trustee and to the Company.

          (d) Any resignation or removal of the Trustee and any appointment of a
successor Trustee pursuant to any of the provisions of this Section shall become
effective upon acceptance of appointment by the successor Trustee as provided in
Section 7.11.

     7.11 Acceptance by Successor Trustee. Any successor Trustee with respect to
all series of Securities appointed as provided in Section 7.10 shall execute,
acknowledge and deliver to the Company and to its predecessor Trustee an
instrument accepting such appointment hereunder, and thereupon the resignation
or removal of the predecessor Trustee with respect to all series shall become
effective and such successor Trustee, without any further act, deed or
conveyance, shall become vested with all the rights, powers, trusts and duties
with respect to such series of its predecessor hereunder, with like effect as if
originally named as Trustee herein; but, on the written request of the Company
or of the successor Trustee, the Trustee ceasing to act shall, upon payment of
any amounts then due it pursuant to the provisions of Section 7.6, execute and
deliver an instrument transferring to such successor Trustee all the rights and
powers with respect to such series of the Trustee so ceasing to act. Upon the
request of any such successor Trustee, the Company shall execute any and all
instruments in writing for more fully and certainly vesting in and confirming to
such successor Trustee all such rights and powers. Any Trustee ceasing to act
shall, nevertheless, retain a lien upon all property or funds held or collected
by such Trustee or any successor Trustee to secure any amounts then due it
pursuant to the provisions of Section 7.6.

     In case of the appointment hereunder of a successor Trustee with respect to
the Securities of one or more (but not all) series, the Company, the retiring
Trustee and each successor Trustee with respect to the Securities of such series
shall execute and deliver an indenture supplemental hereto wherein each
successor Trustee shall accept such appointment and which (1) shall contain such
provisions as shall be necessary or desirable to transfer and confirm to, and to
vest in, each successor Trustee all the rights, powers, trusts and duties of the
retiring Trustee with respect to the Securities of such series to which the
appointment of such successor Trustee relates, (2) if the retiring Trustee is
not retiring with respect to all Securities, shall contain such provisions as
shall be deemed necessary or desirable to confirm that all the rights, powers,
trusts and duties of the retiring Trustee with respect to the Securities of such
series as to which the retiring Trustee is not retiring shall continue to be
vested in the retiring Trustee, and (3) shall add to or change any of the
provisions of this Indenture as shall be necessary to provide for or facilitate
the administration of the trusts hereunder by more than one Trustee, it being
understood that nothing herein or in such supplemental indenture shall
constitute such Trustees co-Trustees of the same trust and that each such
Trustee shall be Trustee of a trust or trusts hereunder separate and apart from
any trust or trusts hereunder administered by any other such Trustee; and upon
the execution and delivery of such supplemental indenture the resignation or
removal of the retiring Trustee shall become effective to the extent provided
therein and each such successor Trustee, without

                                       35

<PAGE>

any further act, deed or conveyance, shall become vested with all the rights,
powers, trusts and duties of the retiring Trustee with respect to the Securities
of such series to which the appointment of such successor Trustee relates; but,
on written request of the Company or any successor Trustee, such retiring
Trustee shall duly assign, transfer and deliver to such successor Trustee all
property and money held by such retiring Trustee hereunder with respect to the
Securities of such series to which the appointment of such successor Trustee
relates.

         No successor Trustee shall accept appointment as provided in this
Section unless at the time of such acceptance such successor Trustee shall be
qualified under the provisions of Section 7.8 and eligible under the provisions
of Section 7.9.

         Upon acceptance of appointment by a successor Trustee as provided in
this Section, the successor Trustee shall at the expense of the Company transmit
notice of the succession of such Trustee hereunder to the holders of Securities
of any applicable series in the manner and to the extent provided in subsection
(c) of Section 5.4 with respect to reports pursuant to subsection (a) of said
Section 5.4.

         7.12  Successor to Trustee by Merger, Consolidation or Succession to
Business. Any corporation into which the Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Trustee shall be a party, or any
corporation succeeding to all or substantially all of the corporate trust
business of the Trustee, shall be the successor of the Trustee hereunder,
provided such corporation shall be qualified under the provisions of Section 7.8
and eligible under the provisions of Section 7.9, without the execution or
filing of any paper or any further act on the part of any of the parties hereto,
anything herein to the contrary notwithstanding.

         In case at the time such successor to the Trustee shall succeed to the
trusts created by this Indenture any of the Securities shall have been
authenticated but not delivered, any such successor to the Trustee may adopt the
certificate of authentication of any predecessor Trustee, and deliver such
Securities so authenticated; and in case at that time any of the Securities
shall not have been authenticated, any successor to the Trustee may authenticate
such Securities either in the name of any predecessor hereunder or in the name
of the successor Trustee; and in all such cases such certificates shall have the
full force which it is anywhere in the Securities or in this Indenture provided
that the certificate of the Trustee shall have; provided, however, that the
right to adopt the certificate of authentication of any predecessor Trustee or
to authenticate Securities in the name of any predecessor Trustee shall apply
only to its successor or successors by merger, conversion or consolidation.

         7.13  Limitations on Preferential Collection of Claims by the Trustee.

         The Trustee shall comply with Section 311(a) of the Trust Indenture Act
of 1939, excluding any creditor relationship described in Section 311(b) of the
Trust Indenture Act of 1939. A Trustee who has resigned or been removed shall be
subject to Section 311(a) of the Trust Indenture Act of 1939 to the extent
included therein.

                                  ARTICLE VIII
                         CONCERNING THE SECURITYHOLDERS

         8.1   Evidence of Action by Securityholders. Whenever in this Indenture
it is provided that the holders of a specified percentage in principal amount of
the Securities of any or all series may take any action (including the making of
any demand or request, the giving of any notice, consent, or waiver or the
taking of any other action), the fact at the time of taking any such action the
holders of such specified percentage have joined therein may be evidenced (a) by
any instrument or any number of instruments of similar tenor executed by such
Securityholders in person or by agent or proxy appointed in writing, or (b) by
the record of such holders of Securities voting in favor thereof at any meeting
of such Securityholders duly called and held in accordance with the

                                       36

<PAGE>

provisions of Article Nine, or (c) by a combination of such instrument or
instruments and any such record of such a meeting of such Securityholders.

         If there shall be more than one Trustee acting hereunder with respect
to separate series of Securities, such Trustees shall collaborate, if necessary,
in acting under Article Nine and in determining whether the holders of a
specified percentage in principal amount of the Securities of any or all series
have taken any such action.

         8.2   Proof of Execution of Instruments and of Holding of Securities.
Subject to the provisions of Sections 7.1, 7.2 and 9.5, proof of the execution
of any instrument by a Securityholder or his agent or proxy and proof of the
holding by any person of any of the Securities shall be sufficient if made in
the following manner:

         The fact and date of the execution by any such person of any instrument
may be proved in any reasonable manner acceptable to the Trustee.

         The ownership of Securities of any series shall be proved by the
Register of such Securities of such series, or by certificates of the Security
registrar thereof.

         The Trustee shall not be bound to recognize any person as a
Securityholder unless and until title to the Securities held by him is proved in
the manner in this Article Eight provided.

         The record of any Securityholders' meeting shall be proved in the
manner provided in Section 9.6.

         The Trustee may accept such other proof or require such additional
proof of any matter referred to in this Section as it shall deem reasonable.

         8.3   Who may be Deemed Owners of Securities. Prior to due presentment
for registration of transfer of any Security, the Company, the Trustee and any
agent of the Company or the Trustee may deem and treat the person in whose name
such Security shall be registered upon the Register of Securities of the series
of which such Security is a part as the absolute owner of such Security (whether
or not payments in respect of such Security shall be overdue and notwithstanding
any notation of ownership or other writing thereon) for the purpose of receiving
payment of or an account of the principal of and interest, subject to Section
2.3, on such Security and for all other purposes; and neither the Company nor
the Trustee nor any agent of the Company or the Trustee shall be affected by any
notice to the contrary. All such payments so made to any such holder for the
time being, or upon his order, shall be valid, and, to the extent of the sum or
sums so paid, effectual to satisfy and discharge the liability for moneys
payable upon any such Security.

         8.4   Securities Owned by Company or Controlled or Controlling Persons
Disregarded for Certain Purposes. In determining whether the holders of the
requisite principal amount of Securities have concurred in any demand,
direction, request, notice, vote, consent, waiver or other action under this
Indenture, Securities which are owned by the Company or any other obligor on the
Securities or by any person directly or indirectly controlling or controlled by
or under direct or indirect common control with the Company or any other obligor
on the Securities shall be disregarded and deemed not to be outstanding for the
purpose of any such determination, provided that for the purposes of determining
whether the Trustee shall be protected in relying on any such demand, direction,
request, notice, vote, consent, waiver or other action, only Securities which a
Responsible Officer of the Trustee assigned to its principal office actually
knows are so owned shall be so disregarded. Securities so owned which have been
pledged in good faith may be regarded as outstanding for the purposes of this
Section, if the pledgee shall establish to the satisfaction of the Trustee the
pledgee's right to vote such Securities and that the pledgee is not a person
directly or indirectly controlling or controlled by or under direct or indirect
common control with the Company or any such other obligor. Upon request of the
Trustee, the Company shall furnish to the Trustee promptly an Officers'
Certificate listing and identifying all Securities, if any, known by the Company
to be owned or held by or for the account of the Company or any other obligor on
the Securities or by any person directly or indirectly controlling or controlled
by or under direct or indirect common control with the Company or any other

                                       37

<PAGE>

obligor on the Securities; and, subject to the provisions of Section 7.1, the
Trustee shall be entitled to accept such Officers' Certificate as conclusive
evidence of the facts therein set forth and of the fact that all Securities not
listed therein are outstanding for the purpose of any such determination.

         8.5   Instruments Executed by Securityholders Bind Future Holders. At
any time prior to (but not after) the evidencing to the Trustee, as provided in
Section 8.1, of the taking of any action by the holders of the percentage in
principal amount of the Securities specified in this Indenture in connection
with such action, any holder of a Security which is shown by the evidence to be
included in the Securities the holders of which have consented to such action
may, by filing written notice with the Trustee at its principal office and upon
proof of holding as provided in Section 8.2, revoke such action so far as
concerns such Security. Except as aforesaid any such action taken by the holder
of any Security and any direction, demand, request, notice, waiver, consent,
vote or other action of the holder of any Security which by any provisions of
this Indenture is required or permitted to be given shall be conclusive and
binding upon such holder and upon all future holders and owners of such
Security, and of any Security issued in lieu thereof or upon registration of
transfer thereof, irrespective of whether any notation in regard thereto is made
upon such Security. Any action taken by the holders of the percentage in
principal amount of the Securities of any or all series specified in this
Indenture in connection with such action shall be conclusively binding upon the
Company, the Trustee and the holders of all of the Securities of such series
subject, however, to the provisions of Section 7.1.

                                   ARTICLE IX
                            SECURITYHOLDERS' MEETINGS

         9.1   Purposes for which Meetings may be Called. A meeting of holders
of Securities of any or all series may be called at any time and from time to
time pursuant to the provisions of this Article for any of the following
purposes:

               (a)  To give any notice to the Company or to the Trustee, or to
give any directions to the Trustee, or to consent to the waiving of any default
hereunder and its consequences, or to take any other action authorized to be
taken by holders of Securities of any or all series, as the case may be,
pursuant to any of the provisions of Article Six;

               (b)  To remove the Trustee and appoint a successor Trustee
pursuant to the provisions of Article Seven;

               (c)  To consent to the execution of an indenture or indentures
supplemental hereto pursuant to the provisions of Section 10.2; or

               (d)  To take any other action authorized to be taken by or on
behalf of the holders of any specified principal amount of the Securities of any
or all series, as the case may be, under any other provision of this Indenture
or under applicable law.

         9.2   Manner of Calling Meetings. The Trustee may at any time call a
meeting of Securityholders to take any action specified in Section 9.1, to be
held at such time and at such place in the Borough of Manhattan, State of New
York, as the Trustee shall determine. Notice of every meeting of Securityholders
setting forth the time and place of such meeting and in general terms the action
proposed to be taken at such meeting, shall be mailed not less than 21 nor more
than 180 days prior to the date fixed for the meeting.

         9.3   Call of Meeting by Company or Securityholders. In case at any
time the Company, pursuant to a resolution of its Board of Directors, or the
holders of not less than 10 percent in principal amount of the Securities of any
or all series, as the case may be, then outstanding, shall have requested the
Trustee to call a meeting of

                                       38

<PAGE>

holders of Securities of any or all series, as the case may be, to take any
action authorized in Section 9.1 by written request setting forth in reasonable
detail the action proposed to be taken at the meeting, and the Trustee shall not
have mailed notice of such meeting within 21 days after receipt of such request,
then the Company or such holders of Securities in the amount above specified may
determine the time and place in the Borough of Manhattan, State of New York for
such meeting and may call such meeting to take any action authorized in Section
9.1, by mailing notice thereof as provided in Section 9.2.

         9.4  Who May Attend and Vote at Meetings. To be entitled to vote at any
meeting of Securityholders a person shall (a) be a holder of one or more
Securities with respect to which the meeting is being held, or (b) be a person
appointed by an instrument in writing as proxy by such holder of one or more
Securities. The only persons who shall be entitled to be present or to speak at
any meeting of Securityholders shall be the persons entitled to vote at such
meeting and their counsel and any representatives of the Trustee and its counsel
and any representatives of the Company and its counsel.

         9.5  Regulations may be made by Trustee. Notwithstanding any other
provisions of this Indenture, the Trustee may make such reasonable regulations
as it may deem advisable for any meeting of Securityholders, in regard to proof
of the holding of Securities and of the appointment of proxies, and in regard to
the appointment and duties of inspectors of votes, the submission and
examination of proxies, certificates and other evidence of the right to vote,
and such other matters concerning the conduct of the meeting as it shall think
fit. Except as otherwise permitted or required by any such regulations, the
holding of Securities shall be proved in the manner specified in Section 8.2 and
the appointment of any proxy shall be proved in the manner specified in said
Section 8.2; provided, however, that such regulations may provide that written
instruments appointing proxies regular on their face, may be presumed valid and
genuine without the proof hereinabove or in said Section 8.2 specified.

         The Trustee shall, by an instrument in writing, appoint a temporary
chairman of the meeting, unless the meeting shall have been called by the
Company or by Securityholders as provided in Section 9.3, in which case the
Company or the Securityholders calling the meeting, as the case may be, shall in
like manner appoint a temporary chairman. A permanent chairman and a permanent
secretary of the meeting shall be elected by majority vote of the meeting.

         Subject to the provisions of Section 8.4, at any meeting each
Securityholder or proxy shall be entitled to one vote for each $1,000 principal
amount of Securities held or represented by him, provided, however, that no vote
shall be cast or counted at any meeting in respect of any Security challenged as
not outstanding and ruled by the permanent chairman of the meeting to be not
outstanding; provided, further, that each holder of Original Issue Discount
Securities shall be entitled to one vote for each $1,000 amount which would be
due upon acceleration of his Original Issue Discount Security on the date of the
meeting. Neither a temporary nor a permanent chairman of the meeting shall have
a right to vote other than by virtue of Securities held by him or instruments in
writing as aforesaid duly designating him as the person to vote on behalf of
other Securityholders. Any meeting of Securityholders duly called pursuant to
the provisions of Section 9.2 or 9.3 may be adjourned from time to time, and the
meeting may be held so adjourned without further notice.

         At any meeting of Securityholders, the presence of persons holding or
representing Securities in principal amount sufficient to take action on the
business for the transaction of which such meeting was called shall constitute a
quorum, but, if less than a quorum is present, the person or persons holding or
representing a majority in principal amount of the Securities represented at the
meeting may adjourn such meeting with the same effect for all intents and
purposes, as though a quorum had been present.

         9.6  Manner of Voting at Meetings and Record to be Kept. The vote upon
any resolution submitted to any meeting of Securityholders shall be by written
ballots on which shall be subscribed the signatures of the holders of Securities
or of their representatives by proxy and the principal amount or principal
amounts of the Securities held or represented by them. The permanent chairman of
the meeting shall appoint two inspectors of votes who shall count all votes cast
at the meeting for or against any resolution and who shall make and file with
the

                                       39

<PAGE>

permanent secretary of the meeting their verified written reports in duplicate
of all votes cast at the meeting. A record in duplicate of the proceedings of
each meeting of Securityholders shall be prepared by the permanent secretary of
the meeting and there shall be attached to said record the original reports of
the inspectors of votes on any vote by ballot taken thereat and affidavits by
one or more persons having knowledge of the facts setting forth a copy of the
notice of the meeting and showing that said notice was mailed as provided in
Section 9.2. The record shall show the principal amount or principal amounts of
the Securities voting in favor of, against, or abstaining from voting on, any
resolution. The record shall be signed and verified by the affidavits of the
permanent chairman and permanent secretary of the meeting and one of the
duplicates shall be delivered to the Company and the other to the Trustee to be
preserved by the Trustee, the latter to have attached thereto the ballots voted
at the meeting.

         Any record so signed and verified shall be conclusive evidence of the
matters therein stated.

         9.7   Exercise of Rights of Trustee, Securityholders and Holders of
Preferred Securities Not to be Hindered or Delayed. Nothing in this Article
contained shall be deemed or construed to authorize or permit, by reason of any
call of a meeting of Securityholders or any rights expressly or impliedly
conferred hereunder to make such call any hindrance or delay in the exercise of
any right or rights conferred upon or reserved to the Trustee, to the
Securityholders or the holders of Preferred Securities under any of the
provisions of this Indenture or of the Securities.

                                    ARTICLE X
                             SUPPLEMENTAL INDENTURES

         10.1  Purposes for which Supplemental Indentures may be Entered into
Without Consent of Securityholders. Without the consent of any Securityholders
or any holders of Preferred Securities, the Company, when authorized by a
Resolution of the Company, and the Trustee may from time to time, and at any
time enter into an indenture or indentures supplemental hereto, in form
satisfactory to such Trustee (which shall comply with the provisions of the
Trust Indenture Act of 1939 as then in effect), for one or more of the following
purposes:

                  (a)  To evidence the succession of another corporation to the
Company, or successive successions, and the assumption by the successor
corporation of the covenants, agreements and obligations of the Company pursuant
to Article Eleven hereof;

                  (b)  To add to the covenants of the Company such further
covenants, restrictions or conditions as the Company and the Trustee shall
consider to be for the protection of the holders of all or any series of
Securities (and if such covenants, restrictions or conditions are to be for the
benefit of less than all series of Securities, stating that such covenants,
restrictions or conditions are expressly being included solely for the benefit
of such series), and to make the occurrence, or the occurrence and continuance,
of a default in any such additional covenants, restrictions or conditions a
default or an Event of Default permitting the enforcement of all or any of the
several remedies provided in this Indenture as herein set forth; provided,
however, that in respect to any such additional covenant, restriction or
condition such supplemental indenture may provide for a particular period of
grace after default (which period may be shorter or longer than that allowed in
the case of other defaults) or may provide for an immediate enforcement upon
such default or may limit the remedies available to the Trustee upon such
default;

                  (c)  To add or change any of the provisions of this Indenture
to such extent as shall be necessary to permit or facilitate the issuance of
Securities in bearer form, registrable or not registrable as to principal, and
with or without interest coupons;

                  (d)  To change or eliminate any of the provisions of this
Indenture; provided, however, that any such change or elimination shall become
effective only when there is no Security of any series outstanding created prior
to the execution of such supplemental indenture which is entitled to the benefit
of such provision;

                                       40

<PAGE>

                (e)  To establish the form or terms of Securities of any
series as permitted by Section 2.1 and 2.2;

                (f)  To cure any ambiguity or to correct or supplement any
provision contained herein or in any supplemental indenture which may be
defective or inconsistent with any other provisions contained herein or in any
supplemental indenture, or to make such other provision in regard to matters or
questions arising under this Indenture or any supplemental indenture; provided,
however, that such action shall not adversely affect the interest of the holders
of Securities of any series in any material respect or, in the case of the
Securities of a series issued to a Markel Capital Trust and for so long as any
of the corresponding series of Preferred Securities issued by such Markel
Capital Trust shall remain outstanding, the holders of such Preferred
Securities;

                (g)  To mortgage or pledge to the Trustee as security for the
Securities any property or assets which the Company may desire to mortgage or
pledge as security for the Securities; and

                (h)  To qualify, or maintain the qualification of, the Indenture
under the Trust Indenture Act.

         The Trustee is hereby authorized to join with the Company in the
execution of any such supplemental indenture, to make any further appropriate
agreements and stipulations which may be therein contained and to accept the
conveyance, transfer, mortgage, pledge or assignment of any property thereunder,
but the Trustee shall not be obligated to enter into any such supplemental
indenture which affects the Trustee's own rights, duties or immunities under
this Indenture or otherwise.

         Any supplemental indenture authorized by the provisions of this Section
may be executed by the Company and the Trustee without the consent of the
holders of any of the Securities at the time outstanding, notwithstanding any of
the provisions of Section 10.2.

         10.2   Modification of Indenture with Consent of Holders of a Majority
in Principal Amount of Securities. With the consent (evidenced as provided in
Section 8.1) of the holders of not less than a majority in principal amount of
the Securities of all series at the time outstanding (determined as provided in
Section 8.4) affected by such supplemental indenture (voting as one class), the
Company, when authorized by a Resolution of the Company, and the Trustee may
from time to time and at any time enter into an indenture or indentures
supplemental hereto (which shall be in conformity with the provisions of the
Trust Indenture Act of 1939 as then in effect) for the purpose of adding any
provisions to or changing in any manner or eliminating any of the provisions of
this Indenture or of any supplemental indenture or of modifying in any manner
the rights of the holders of the Securities of each such series; provided,
however, that no such supplemental indenture shall (i) change the fixed Maturity
of any Securities, or reduce the rate or extend the time of payment of any
interest thereon or on any overdue principal amount or reduce the principal
amount thereof, or change the provisions pursuant to which the rate of interest
on any Security is determined if such change could reduce the rate of interest
thereon, or reduce the minimum rate of interest thereon, or reduce any amount
payable upon any redemption thereof, or adversely affect any right to convert
the Securities in accordance therewith, or reduce the amount to be paid at
Maturity or upon redemption in Capital Stock or make the principal thereof or
any interest thereon or on any overdue principal amount payable in any coin or
currency other than that provided in the Security without the consent of the
holder of each Security so affected, (ii) reduce the aforesaid percentage of
Securities, the holders of which are required to consent to any such
supplemental indenture without the consent of the holders of all Securities then
outstanding, (iii) modify any of the provisions of this Section, Section 4.6 or
Section 6.6, except to increase any such percentage or to provide that certain
other provisions of this Indenture cannot be modified or waived without the
consent of the holders of all Securities then outstanding or (iv) modify the
provisions of Article Fourteen with respect to the subordination of outstanding
Securities of any series in a manner adverse to the holders thereof without the
consent of the holder of each Security so affected; provided, however, that, in
the case of the Securities of a series issued to a Markel Capital Trust, so long
as any of the corresponding series of Preferred Securities issued by such Markel
Capital Trust remains outstanding, (i) no such amendment shall be made that
adversely affects the holders of such Preferred Securities in any material
respect, and no termination of this Indenture shall occur, and no waiver of any
Event of Default with

                                       41

<PAGE>

respect to such series or compliance with any covenant with respect to such
series under this Indenture shall be effective, without the prior consent of the
holders of at least a majority of the aggregate liquidation amount of such
Preferred Securities then outstanding unless and until the principal (and
premium, if any) of the Securities of such series and all accrued and unpaid
interest (including any Additional Interest) thereon have been paid in full; and
(ii) no amendment shall be made to Section 6.5 of this Indenture that would
impair the rights of the holders of such Preferred Securities provided therein
or to this Indenture that requires the consent of each holder of the Securities
of such series without the prior consent of each holder of such Preferred
Securities then outstanding unless and until the principal (and premium, if any)
of the Securities of such series and all accrued and unpaid interest (including
any Additional Interest) thereon have been paid in full.

         A supplemental indenture which changes or eliminates any covenant or
other provision of this Indenture which has expressly been included solely for
the benefit of one or more particular series of Securities or Preferred
Securities, or which modifies the rights of holders of Securities or holders of
Preferred Securities of such series with respect to such covenant or other
provision, shall be deemed not to affect the rights under this Indenture of the
holders of Securities or holders of Preferred Securities of any other series.

         Upon the request of the Company, accompanied by a copy of a Resolution
of the Company certified by the Corporate Secretary or an Assistant Corporate
Secretary of the Company authorizing the execution of any such supplemental
indenture, and upon the filing with the Trustee of evidence of the consent of
Securityholders as aforesaid, the Trustee shall join with the Company in the
execution of such supplemental indenture unless such supplemental indenture
affects the Trustee's own rights, duties or immunities under this Indenture or
otherwise, in which case the Trustee may in its discretion, but shall not be
obligated to, enter into such supplemental indenture.

         It shall not be necessary for the consent of the Securityholders under
this Section to approve the particular form of any proposed supplemental
indenture, but it shall be sufficient if such consent shall approve the
substance thereof.

         Promptly after the execution by the Company and the Trustee of any
supplemental indenture pursuant to the provisions of this Section, the Company
shall mail a notice to the holders of Securities of each series so affected,
setting forth in general terms the substance of such supplemental indenture. Any
failure of the Company to mail such notice, or any defect therein, shall not,
however, in any way impair or affect the validity of any such supplemental
indenture.

         10.3  Effect of Supplemental Indentures. Upon the execution of any
supplemental indenture pursuant to the provisions of this Article, this
Indenture shall be and be deemed to be modified and amended in accordance
therewith and the respective rights, limitations of rights, obligations, duties
and immunities under this Indenture of the Trustee, the Company and the holders
of Securities shall thereafter be determined, exercised and enforced hereunder
subject in all respects to such modifications and amendments, and all the terms
and conditions of any such supplemental indenture shall be and be deemed to be
part of the terms and conditions of this Indenture for any and all purposes.

         The Trustee shall be entitled to receive, and subject to the provisions
of Section 7.1 shall be entitled to rely upon, an Opinion of Counsel as
conclusive evidence that any such supplemental indenture complies with the
provisions of this Article and all conditions precedent have been complied with
by the Company.

         10.4  Securities May Bear Notation of Changes by Supplemental
Indentures. Securities authenticated and delivered after the execution of any
supplemental indenture pursuant to the provisions of this Article, or after any
action taken at a Securityholders' meeting pursuant to Article Nine, may bear a
notation in form approved by the Trustee as to any matter provided for in such
supplemental indenture or as to any action taken at any such meeting. If the
Company or the Trustee shall so determine, new Securities so modified as to
conform, in the opinion of the Trustee and the Board of Directors of the
Company, to any modification of this Indenture

                                       42

<PAGE>

contained in any such supplemental indenture may be prepared by the Company,
authenticated by the Trustee and delivered in exchange for the Securities then
outstanding.

         10.5  Revocation and Effect of Consents. Subject to Section 8.5, until
an amendment, supplement, waiver or other action becomes effective, a consent to
it by a Securityholder of a Security is a continuing consent conclusive and
binding upon such Securityholder and every subsequent Securityholder of the same
Security or portion thereof, and of any Security issued upon the registration of
transfer thereof or in exchange therefor or in place thereof, even if notation
of the consent is not made on any such Security.

         The Company may, but shall not be obligated to, fix a record date for
the purpose of determining the Securityholders entitled to consent to any
amendment, supplement or waiver. If a record date is fixed, then,
notwithstanding the preceding paragraph, those Persons who were Securityholders
at such record date (or their duly designated proxies), and only such Persons,
shall be entitled to consent or revoke such consent to such amendment,
supplement or waiver, whether or not such Persons continue to be Securityholders
after such record date. No such consent shall be valid or effective for more
than 180 days after such record date.

         After an amendment, supplement, waiver or other action becomes
effective, it shall bind every Securityholder.

         10.6  Conformity with Trust Indenture Act.  Every supplemental
indenture executed pursuant to this Article shall conform to the requirements of
the Trust Indenture Act.


                                   ARTICLE XI
                    CONSOLIDATION, MERGER, SALE OR CONVEYANCE

         11.1  Company May Consolidate, Etc., Only on Certain Terms.

         The Company shall not consolidate with or merge into, or transfer all
or substantially all of its assets to, any Person, unless:

         (1)   the Person expressly assumes, by an indenture supplemental
hereto, executed and delivered to the Trustee and in form satisfactory to the
Trustee, the due and punctual payment of the principal of and any premium and
interest on all the Securities and the performance of every covenant of this
Indenture on the part of the Company to be performed or observed;

         (2)   immediately after giving effect to such transaction, no Event of
Default, and no event which, after notice or lapse of time, or both, would
become an Event of Default, shall have happened and be continuing; and

         (3)   the Company has delivered to the Trustee an Officers' Certificate
and an Opinion of Counsel each stating that such consolidation, merger or
transfer and such supplemental indenture, if any, comply with this Article and
that all conditions precedent herein provided for relating to such transaction
have been complied with.

         11.2  Successor Person Substituted for Company.

         Upon the Company's consolidation with or merger into, or the transfer
of all or substantially all of the Company's assets to, any Person in accordance
with Section 11.2, such Person shall succeed to, and be substituted for, and may
exercise every right and power of, the Company under this Indenture with the
same effect as if such Person had been named as the Company herein; and in the
case of a transfer of all or substantially all of its assets, the Company (which
term shall for this purpose mean the Person named as the "Company" in the first
paragraph of this Indenture or any successor which shall become such in the
manner described in Section 11.2) shall be

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<PAGE>

discharged from all obligations and covenants under this Indenture, the
Securities and the Coupons and may be dissolved and liquidated.

                                   ARTICLE XII
            SATISFACTION AND DISCHARGE OF INDENTURE, UNCLAIMED MONEYS

         12.1  Satisfaction and Discharge of Indenture. If (a) the Company shall
deliver to the Trustee for cancellation all Securities of any series theretofore
authenticated (other than any Securities of such series which shall have been
destroyed, lost or stolen and which shall have been replaced or paid as provided
in Section 2.7) and not theretofore canceled, or (b) all the Securities of such
series not theretofore canceled or delivered to the Trustee for cancellation
shall have become due and payable, or are by their terms to become due and
payable within one year or are to be called for redemption within one year under
arrangements satisfactory to the Trustee for the giving of notice of redemption,
and the Company shall deposit with the Trustee as trust funds the entire amount
sufficient to pay at Maturity or upon redemption all of such Securities not
theretofore canceled or delivered to the Trustee for cancellation, including
principal and any interest due or to become due to such date of Maturity or
redemption date, as the case may be, and if in either case the Company shall
also pay or cause to be paid all other sums payable hereunder by the Company
with respect to Securities of such series, then this Indenture shall cease to be
of further effect with respect to Securities of such series, (except as to (i)
remaining rights of registration of transfer, conversion, substitution and
exchange and the Company's right of optional redemption of Securities of such
series, (ii) rights hereunder of holders to receive payments of principal of,
and any interest on, the Securities of such series, and other rights, duties and
obligations of the holders of Securities of such series as beneficiaries hereof
with respect to the amounts, if any, so deposited with the Trustee, and (iii)
the rights, obligations and immunities of the Trustee hereunder), and the
Trustee, on demand of the Company, and at the cost and expense of the Company,
shall execute proper instruments acknowledging satisfaction of and discharging
this Indenture. The Company hereby agrees to compensate the Trustee for any
services thereafter reasonably and properly rendered and to reimburse the
Trustee for any costs or expenses theretofore and thereafter reasonably and
properly incurred by the Trustee in connection with this Indenture or the
Securities of such series.

         Notwithstanding the satisfaction and discharge of this Indenture with
respect to the Securities of any or all series, the obligations of the Company
to the Trustee under Section 7.6 shall survive.

         12.2  Application by Trustee of Funds Deposited for Payment of
Securities. Subject to Section 12.4, all moneys deposited with the Trustee
pursuant to Section 12.1 shall be held in trust and applied by it to the
payment, either directly or through any Paying Agent (including the Company
acting as its own Paying Agent), to the holders of the particular Securities of
such series, for the payment or redemption of which such moneys have been
deposited with the Trustee, of all sums due and to become due thereon for
principal and interest.

         12.3  Repayment of Moneys Held by Paying Agent. In connection with the
satisfaction and discharge of this Indenture with respect to Securities of any
series, all moneys with respect to Securities of such series then held by any
Paying Agent under the provisions of this Indenture shall, upon demand of the
Company, be paid to the Trustee and thereupon such Paying Agent shall be
released from all further liability with respect to such moneys.

         12.4  Repayment of Moneys Held by Trustee. Any moneys deposited with
the Trustee or any Paying Agent for the payment of the principal of or any
interest on any Securities of any series and not applied but remaining unclaimed
by the holders of Securities of such series for two years after the date upon
which such payment shall have become due and payable, shall, at the request of
the Company, be repaid to the Company by the Trustee or by such Paying Agent;
and the holder of any of the Securities of such series entitled to receive such
payment shall thereafter look only to the Company for the payment thereof;
provided, however, that the Trustee or such Paying Agent, before being required
to make any such repayment, may at the expense of the Company cause to be
published once a week for two successive weeks (in each case on any day of the
week) in an Authorized

                                       44

<PAGE>

Newspaper, or mailed to the registered holders thereof, a notice that said
moneys have not been so applied and that after a date named therein any
unclaimed balance of said money then remaining will be returned to the Company.

                                  ARTICLE XIII
               IMMUNITY OF INCORPORATORS, STOCKHOLDERS, OFFICERS,
                             DIRECTORS AND EMPLOYEES

         13.1  Incorporators, Stockholders, Officers, Directors and Employees of
Company Exempt from Individual Liability. No recourse under or upon any
obligation, covenant or agreement of this Indenture, or of any Security, or for
any claim based thereon or otherwise in respect thereof, shall be had against
any incorporator, stockholder, officer, director or employee, as such, past,
present or future, of the Company or of any successor corporation, either
directly or through the Company, whether by virtue of any constitution, statute
or rule of law, or by the enforcement of any assessment or penalty or otherwise,
it being expressly understood that this Indenture and the obligations issued
hereunder are solely corporate obligations, and that no personal liability
whatever shall attach to, or is or shall be incurred by, the incorporators,
stockholders, officers, directors or employees, as such, of the Company or any
successor corporation, or any of them, because of the creation of the
indebtedness hereby authorized, or under or by reason of the obligations,
covenants or agreements contained in this Indenture or in any of the Securities
or implied therefrom; and that any and all such personal liability of every name
and nature, either at common law or in equity or by constitution or statute, of,
and any and all such rights and claims against every such incorporator,
stockholder, officer, director or employee, as such, because of the creation of
the indebtedness hereby authorized, or under or by reason of the obligations,
covenants or agreements contained in this Indenture or in any of the Securities
or implied therefrom are hereby expressly waived and released as a condition of
and as a consideration for, the execution of this Indenture and the issue of
such Securities.

                                   ARTICLE XIV
                           SUBORDINATION OF SECURITIES

         14.1  Agreement to Subordinate. The Company, for itself, is successors
and assigns, covenants and agrees, and each holder of a Security of any series
likewise covenants and agrees by his acceptance thereof, that the obligation of
the Company to make any payment on account of the principal of and interest on
each and all of the Securities of any series shall be subordinate and junior in
right of payment to the Company's obligations to the holders of Senior
Indebtedness of the Company.

         In the case of any insolvency, receivership, conservatorship,
reorganization, readjustment of debt, marshaling of assets and liabilities or
similar proceedings or any liquidation or winding-up of or relating to the
Company as a whole, whether voluntary or involuntary, all obligations of the
Company to holders of Senior Indebtedness of the Company shall be entitled to be
paid in full before any payment shall be made on account of the principal of or
interest on any of the Securities. In the event of any such proceeding, after
payment in full of all sums owing with respect to Senior Indebtedness of the
Company, the holders of the Securities of each series, together with the holders
of any obligations of the Company ranking on a parity with the Securities, shall
be entitled to be paid from the remaining assets of the Company the amounts at
the time due and owing on account of unpaid principal of and interest on the
Securities of any series before any payment or other distribution, whether in
cash, property or otherwise, shall be made on account of any capital stock or
any obligations of the Company ranking junior to the Securities. In addition, in
the event of any such proceeding, if any payment or distribution of assets of
the Company of any kind or character whether in cash, property or securities,
including any such payment or distribution which may be payable or deliverable
by reason of the payment of any other indebtedness of the Company being
subordinated to the payment of the Securities of any series shall be received by
the Trustee or the holders of the Securities of any series before all Senior
Indebtedness of the Company is paid in full, such payment or distribution shall
be held in trust for the benefit of and shall be paid over to the holders of
such Senior Indebtedness of the Company or their representative or
representatives or to the trustee or trustees under any indenture under

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<PAGE>

which any instruments evidencing any of such Senior Indebtedness of the Company
may have been issued, ratably, for application to the payment of all Senior
Indebtedness of the Company remaining unpaid until all such Senior Indebtedness
of the Company shall have been paid in full, after giving effect to any
concurrent payment or distribution to the holders of such Senior Indebtedness of
the Company. The obligations of the Company in respect of the Securities of all
series shall rank on a parity with any obligations of the Company ranking on a
parity with the Securities. Nothing in this Article shall apply to claims of, or
payments to, the Trustee under or pursuant to Section 7.6.

         The subordination provisions of the foregoing paragraph and Section
14.9 shall not be applicable to amounts at the time due and owing on the
Securities of any series on account of the unpaid principal of or interest on
the Securities of such series for the payment of which funds have been deposited
in trust with the Trustee or any Paying Agent or have been set aside by the
Company in trust in accordance with the provisions of this Indenture; nor shall
such provisions impair any rights, interests, or powers of any secured creditor
of the Company in respect of any security the creation of which is not
prohibited by the provisions of this Indenture.

         The Company shall give written notice to the Trustee within 10 Business
Days after the occurrence of (i) any insolvency, receivership, conservatorship,
reorganization, readjustment of debt, marshaling of assets and liabilities or
similar proceedings or any liquidation or winding-up of or relating to the
Company as a whole, whether voluntary or involuntary, (ii) any Event of Default
described in 6.1(d) or 6.1(e), or (iii) any event specified in Section 14.9. The
Trustee, subject to the provisions of Section 7.1, shall be entitled to assume
that, and may act as if, no such event referred to in the preceding sentence has
occurred unless a Responsible Officer of the Trustee assigned to the Trustee's
corporate trust department has received at the principal office of the Trustee
from the Company or any one or more holders of Senior Indebtedness of the
Company or any trustee or representative therefor (who shall have been certified
or otherwise established to the satisfaction of the Trustee to be such a holder
or trustee or representative) written notice thereof. Upon any distribution of
assets of the Company referred to in this Article, the Trustee and holders of
the Securities of each series shall be entitled to rely upon any order or decree
of a court of competent jurisdiction in which proceedings relating to any event
specified in the first sentence of this paragraph are pending for the purpose of
ascertaining the persons entitled to participate in such distribution, the
holders of the Senior Indebtedness of the Company, the amount thereof or payable
thereon, the amount or amounts paid or distributed thereon, and all other facts
pertinent thereto or to this Article, and the Trustee, subject to the provisions
of Article Seven, and the holders of the Securities of each series shall be
entitled to rely upon a certificate of the liquidating trustee or agent or other
person making any distribution to the Trustee or to the holders of the
Securities of each series for the purpose of ascertaining the persons entitled
to participate in such distribution, the holders of the Senior Indebtedness of
the Company, the amount thereof or payable thereon, the amount or amounts paid
or distributed thereon and all other facts pertinent thereto or to this Article.
In the absence of any such liquidating trustee, agent or other person, the
Trustee shall be entitled to rely upon a written notice by a Person representing
himself to be a holder of Senior Indebtedness of the Company (or a trustee or
representative on behalf of such holder) as evidence that such Person is a
holder of such Senior Indebtedness (or is such a trustee or representative). In
the event that the Trustee determines, in good faith, that further evidence is
required with respect to the right of any Person, as a holder of Senior
Indebtedness of the Company, to participate in any payment or distribution
pursuant to this Article, the Trustee may request such Person to furnish
evidence to the reasonable satisfaction of the Trustee as to the amount of such
Senior Indebtedness held by such Person, as to the extent to which such Person
is entitled to participation in such payment or distribution, and as to other
facts pertinent to the rights of such Person under this Article, and if such
evidence is not furnished, the Trustee may defer any payment to such Person
pending judicial determination as to the right of such Person to receive such
payment.

         14.2 Obligation of the Company Unconditional. Nothing contained in this
Article or elsewhere in this Indenture is intended to or shall impair, as
between the Company and the holders of the Securities of each series, the
obligation of the Company, which is absolute and unconditional, to pay to such
holders the principal of and interest on such Securities of each series when,
where and as the same shall become due and payable, all in accordance with the
terms of such Securities, or is intended to or shall affect the relative rights
of such holders and creditors of the Company other than the holders of the
Senior Indebtedness of the Company, nor shall anything

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<PAGE>

herein or therein prevent the Trustee or the holder of any Security from
exercising all remedies otherwise permitted by applicable law upon default under
this Indenture, subject to the rights, if any, under this Article of the holders
of Senior Indebtedness of the Company in respect of cash, property, or
securities of the Company received upon the exercise of any such remedy.

         14.3 Limitations on Duties to Holders of Senior Indebtedness of the
Company. With respect to the holders of Senior Indebtedness of the Company, the
Trustee undertakes to perform or to observe only such of its covenants and
obligations as are specifically set forth in this Article, and no implied
covenants or obligations with respect to the holders of Senior Indebtedness of
the Company shall be read into this Indenture against the Trustee. The Trustee
shall not be deemed to owe any fiduciary duty to the holders of Senior
Indebtedness of the Company, except with respect to moneys held in trust
pursuant to the first paragraph of Section 14.1.

         14.4 Notice to Trustee of Facts Prohibiting Payment. Notwithstanding
any of the provisions of this Article or any other provisions of this Indenture,
the Trustee shall not at any time be charged with knowledge of the existence of
any facts which would prohibit the making of any payment of moneys to or by the
Trustee unless and until a Responsible Officer of the Trustee assigned to its
corporate trust department shall have received at the principal office of the
Trustee written notice thereof from the Company or from one or more holders of
Senior Indebtedness of the Company or from any trustee therefor or
representative thereof who shall have been certified by the Company or otherwise
established to the reasonable satisfaction of the Trustee to be such a holder or
trustee or representative; and, prior to the receipt of any such written notice,
the Trustee, subject to the provisions of Section 7.1, shall be entitled in all
respects to assume that no such facts exist; provided, however, that, if prior
to the fifth Business Day preceding the date upon which by the terms hereof any
such moneys may become payable for any purpose, or in the event of the execution
of an instrument pursuant to Section 12.1 acknowledging satisfaction and
discharge of this Indenture, then if prior to the second Business Day preceding
the date of such execution, the Trustee shall not have received with respect to
such moneys the notice provided for in this Section, then, anything herein
contained to the contrary notwithstanding, the Trustee shall have full power and
authority to receive such moneys and/or apply the same to the purpose for which
they were received, and shall not be affected by any notice to the contrary
which may be received by it on or after such date; provided, however, no such
application shall affect the obligations under this Article of the Persons
receiving such moneys from the Trustee.

         14.5 Application by Trustee of Moneys Deposited with It. Anything in
this Indenture to the contrary notwithstanding, any deposit of moneys by the
Company with the Trustee or any agent (whether or not in trust) for any payment
of the principal of or interest on any Securities shall, except as provided in
Section 14.4, be subject to the provisions of Section 14.1.

         14.6 Subrogation. Subject to the payment in full of all Senior
Indebtedness of the Company, the holders of the Securities of each series shall
be subrogated to the rights of the holders of such Senior Indebtedness to
receive payments or distributions of assets of the Company applicable to such
Senior Indebtedness until the Securities shall be paid in full, and none of the
payments or distributions to the holders of such Senior Indebtedness to which
the holders of the Securities of any series or the Trustee would be entitled
except for the provisions of this Article or of payments over pursuant to the
provisions of this Article to the holders of such Senior Indebtedness by the
holders of such Securities or the Trustee shall, as among the Company, its
creditors other than the holders of such Senior Indebtedness, and the holders of
such Securities, be deemed to be a payment by the Company to or on account of
such Senior Indebtedness; it being understood that the provisions of this
Article are and are intended solely for the purpose of defining the relative
rights of the holders of such Securities, on the one hand, and the holders of
the Senior Indebtedness of the Company, on the other hand.

         14.7 Subordination Rights Not Impaired by Acts or Omissions of Company
or Holders of Senior Indebtedness of the Company. No right of any present or
future holders of any Senior Indebtedness of the Company to enforce
subordination as herein provided shall at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act
or failure to act, in good faith, by any such holder, or by any noncompliance by
the Company with the terms, provisions and covenants of this Indenture,
regardless of any

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<PAGE>

knowledge thereof with which any such holder may have or be otherwise charged.
The holders of Senior Indebtedness of the Company may, at any time or from time
to time and in their absolute discretion, change the manner, place or terms of
payment, change or extend the time of payment of, or renew or alter, any such
Senior Indebtedness of the Company, or amend or supplement any instrument
pursuant to which any such Senior Indebtedness of the Company is issued or by
which it may be secured, or release any security therefor, or exercise or
refrain from exercising any other of their rights under the Senior Indebtedness
of the Company including, without limitation, the waiver of default thereunder,
all without notice to or assent from the holders of the Securities of each
series or the Trustee and without affecting the obligations of the Company, the
Trustee or the holders of such Securities under this Article.

         14.8  Authorization of Trustee to Effectuate Subordination of
Securities. Each holder of a Security of any series, by his acceptance thereof,
authorizes and expressly directs the Trustee on his behalf to take such action
as may be necessary or appropriate to effectuate, as between the holders of such
Securities and the holders of Senior Indebtedness of the Company, the
subordination provided in this Article. If, in the event of any proceeding or
other action relating to the Company referred to in the second paragraph of
Section 14.1, a proper claim or proof of debt in the form required in such
proceeding or action is not filed by or on behalf of the holders of the
Securities of any series prior to fifteen days before the expiration of the time
to file such claim or claims, then the holder or holders of Senior Indebtedness
of the Company shall have the right to file and are hereby authorized to file an
appropriate claim for and on behalf of the holders of such Securities.

         14.9  No Payment when Senior Indebtedness in Default. In the event and
during the continuation of any default in the payment of principal of or
interest on any Senior Indebtedness, or in the event that any event of default
with respect to any Senior Indebtedness shall have occurred and be continuing
and shall have resulted in such Senior Indebtedness becoming or being declared
due and payable prior to the date on which it would otherwise have become due
and payable, unless and until such event of default shall have been cured,
waived or remedied or shall have ceased to exist and such acceleration shall
have been rescinded or annulled or all amounts due on such Senior Indebtedness
are paid in full in cash or other permitted consideration, or in the event any
judicial proceeding shall be pending with respect to any such default in payment
or such event or default (unless and until all amounts due on such Senior
Indebtedness are paid in full in cash or other permitted consideration), then no
payment or distribution of any kind or character, whether in cash, properties or
securities shall be made by the Company on account of principal of (or premium,
if any) or interest (including any Additional Interest) if any, on the
Securities or on account of the purchase or other acquisition of Securities by
the Company or any Subsidiary.

         In the event that, notwithstanding the foregoing, the Company shall
make any payment to the Trustee or the holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to the Trustee or, as the case may
be, such holder, then and in such event payment shall be paid over and delivered
forthwith to the Company.

         14.10 Right of Trustee to Hold Senior Indebtedness of the Company. The
Trustee shall be entitled to all of the rights set forth in this Article in
respect of any Senior Indebtedness of the Company at any time held by it in its
individual capacity to the same extent as any other holder of such Senior
Indebtedness, and nothing in this Indenture shall be construed to deprive the
Trustee of any of its rights as such holder.

         14.11 Article Fourteen Not to Prevent Defaults. The failure of the
Company to make a payment pursuant to the terms of Securities of any series by
reason of any provision in this Article shall not be construed as preventing the
occurrence of an Event of Default under this Indenture.

                                   ARTICLE XV
                            MISCELLANEOUS PROVISIONS

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<PAGE>

         15.1 Successors and Assigns of Company Bound by Indenture. All the
covenants, stipulations, promises and agreements in this Indenture contained by
or in behalf of the Company shall bind its successors and assigns, whether so
expressed or not.

         15.2 Acts of Board, Committee or Officer of Successor Corporation
Valid. Any act or proceeding by any provision of this Indenture authorized or
required to be done or performed by any board, committee or officer or officers
of the Company shall and may be done and performed with like force and effect by
the like board, committee or officer or officers of any corporation that shall
at the time be the lawful sole successor of the Company.

         15.3 Required Notices or Demands may be Served by Mail. Any notice or
demand which by any provisions of this Indenture is required or permitted to be
given or served by the Trustee, by the holders of Securities or by the holders
of Preferred Securities to or on the Company may be given or served by
registered mail postage prepaid addressed (until another address is filed by the
Company with the Trustee for such purpose), as follows: Markel Corporation, 4521
Highwoods Parkway, Glen Allen, Virginia 23060, Attention: General Counsel. Any
notice, direction, request, demand, consent or waiver by the Company, by any
Securityholder or by any holder of a Preferred Security to or upon the Trustee
shall be deemed to have been sufficiently given, made or filed, for all
purposes, if given, made or filed in writing at the principal corporate trust
office of the Trustee, 450 West 33rd Street, New York, New York 10001 Attention:
Institutional Trust Services.

         15.4 Officers' Certificate and Opinion of Counsel to be Furnished upon
Applications or Demands by the Company. Except as otherwise expressly provided
in this Indenture, upon any application or request by the Company to the Trustee
to take any action under any provision of this Indenture, the Company shall
furnish to the Trustee an Officers' Certificate stating that all conditions
precedent, if any, provided for in this Indenture relating to the proposed
action have been complied with and an Opinion of Counsel stating that, in the
opinion of such counsel, such action is authorized or permitted by this
Indenture and that all such conditions precedent, if any, have been complied
with, except that in the case of any such application or request as to which the
furnishing of such documents or any of them is specifically required by any
provision of this Indenture relating to such particular application or request,
no additional certificate or opinion need be furnished.

         15.5 Payments Due on Saturdays, Sundays, and Holidays. In any case
where the date of payment of interest on or principal of the Securities of any
series or the date fixed for any redemption of any Security of any series shall
not be a Business Day, then payment of interest or principal need not be made on
such date, but shall be made on the next succeeding Business Day with the same
force and effect as if made on the date fixed for the payment of interest on or
principal of the Security or the date fixed for any redemption of any Security
of such series, and no additional interest shall accrue for the period after
such date and before payment.

         15.6 Provisions Required by Trust Indenture Act of 1939 to Control. If
and to the extent that any provision of this Indenture limits, qualifies or
conflicts with another provision included in this Indenture which is required to
be included in this Indenture by any of Sections 310 to 317, inclusive, of the
Trust Indenture Act through operation of Section 318 thereof, such required
provision shall control.

         15.7 Indenture and Securities to be Construed in Accordance with the
Laws of the State of New York. This Indenture and each Security shall be
governed by the laws of the State of New York, and for all purposes shall be
construed in accordance with the laws of said State (without regard to conflicts
of laws principles thereof).

         15.8 Provisions of the Indenture and Securities for the Sole Benefit of
the Parties and the Securityholders. Nothing in this Indenture or in the
Securities, expressed or implied, shall give or be construed to give any person,
firm or corporation, other than the parties hereto, their successors and
assigns, the holders of the Securities, and the holders of any Senior
Indebtedness of the Company, any legal or equitable right, remedy or claim under
or in respect of this Indenture, or under any covenant, condition and provision
herein contained; all its

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<PAGE>

covenants, conditions and provisions being for the sole benefit of the parties
hereto and their successors and assigns and of the holders of the Securities
and, to the extent expressly provided in Sections 4.8, 6.1, 6.5, 6.6, 9.7, 10.1
and 10.2, the holders of Preferred Securities.

     15.9  Indenture may be Executed in Counterparts. This Indenture may be
executed in any number of counterparts, each of which shall be an original; but
such counterparts shall together constitute but one and the same instrument.

     15.10 Securities in Foreign Currencies. Whenever this Indenture provides
for any action by, or any distribution to, holders of Securities denominated in
United States dollars and in any other currency, in the absence of any provision
to the contrary in the form of Security of any particular series, the relative
amount in respect of any Security denominated in a currency other than United
States dollars shall be treated for any such action or distribution as that
amount of United States dollars that could be obtained for such amount on such
reasonable basis of exchange and as of such date as the Company may specify in a
written notice to the Trustee.

     15.11 Table of Contents, Headings, etc. The Table of Contents and the
titles and headings of the articles and sections of this Indenture have been
inserted for convenience of reference only, are not to be considered a part
hereof, and shall in no way modify or restrict any of the terms or provisions
hereof.

     The Chase Manhattan Bank, hereby accepts the trusts in this Indenture
declared and provided, upon the terms and conditions, hereinabove set forth.

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<PAGE>

         IN WITNESS WHEREOF, MARKEL CORPORATION, has caused this Indenture to be
signed and acknowledged by its [Vice President], and THE CHASE MANHATTAN BANK,
has caused this Indenture to be signed and acknowledged by its
_________________________________________, all as of the day and year first
written above.

                                            MARKEL CORPORATION


                                            By: _______________________________
                                            Name:
                                            Title: Vice President


                                            THE CHASE MANHATTAN BANK, as trustee


                                            By: _______________________________
                                            Name:
                                            Title:

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