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                                 Exhibit 10 X

                     Option Agreement dated March 2, 2001
                           with Edward J. Kelly, III
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                                                                    Exhibit 10 X

                       MERCANTILE BANKSHARES CORPORATION
                               OPTION AGREEMENT

         This Option Agreement is entered into this 2nd day of March, 2001, by
and between Mercantile Bankshares Corporation ("MBC"), a Maryland corporation,
and Edward J. Kelly, III ("Grantee").

                                   ARTICLE 1

                                  DEFINITIONS

          For the purposes of this Agreement, the definitions set forth in
Sections 1.1 through 1.27 shall be applicable.

          Section 1.1 Affiliate. "Affiliate" shall mean: (i) any corporation in
          ---------------------
which MBC owns, directly or indirectly, within the meaning of (S)424(f) of the
Code, fifty percent (50%) or more of the total combined voting power of all
classes of stock of such corporation on a Grant Date; and (ii) any parent
corporation of MBC, within the meaning of (S)424(e) of the Code.

          Section 1.2 Agreement. "Agreement" shall mean this Option Agreement
          ---------------------
and shall include the Plan, which is hereby incorporated into and made a part of
the Agreement.

          Section 1.3 Anniversary Date. "Anniversary Date" shall mean March 1st
          ----------------------------
of each of the first four years after the Grant Date.

          Section 1.4 Anniversary Date Option Amount. "Anniversary Date Option
          ------------------------------------------
Amount" shall mean twenty-five percent (25%) of the Option Amount.

          Section 1.5 Base Year. "Base Year" shall mean the 1999 calendar year.
          ----------------------

          Section 1.6 Board. "Board" shall mean the Board of Directors of MBC.
          ------------------

          Section 1.7 Calculation Year. "Calculation Year" shall mean the
          ----------------------------
calendar year ending immediately prior to the calendar year in which an
Anniversary Date falls.
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          Section 1.8  Code. "Code" shall mean the Internal Revenue Code of
          -----------------
1986, as amended, and any regulations issued thereunder.

          Section 1.9  Committee. "Committee" shall mean the Committee appointed
          ----------------------
pursuant to Section 3.3 of the Plan.

          Section 1.10 Disability. "Disability" shall mean Grantee's inability
          -----------------------
to engage in any substantial gainful activity, by reason of any medically
determined physical or mental impairment that may be expected to result in death
or that has lasted or may be expected to last for a continuous period of not
less than twelve (12) months, as determined by the Committee based on proof of
the existence of such disability in such form and manner and at such times as
the Committee may require.

          Section 1.11 Earnings. "Earnings" shall mean the earnings per share of
          ---------------------
Stock for a calendar year (including the Base Year), as reported in the Annual
Report to Shareholders for such calendar year and as may be adjusted by the
Committee in its discretion.

          Section 1.12 Earnings AGR. "Earnings AGR" shall mean the annual rate
          -------------------------
of growth in Earnings, expressed as a percentage (with any fraction of a percent
of 0.50% or more being rounded up to the nearest whole percent), determined in
accordance with the following formula:

                                  (A-B)(100)
                                  ----------
                                       B

where "A" equals Earnings for the Calculation Year, and "B" equals Earnings for
the calendar year immediately preceding the Calculation Year.

          Section 1.13 Earnings CGR. "Earnings CGR" shall mean the compounded
          -------------------------
growth rate of Earnings and shall be determined by calculating the rate of
interest at

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which Earnings for the Base Year would have to be invested to yield the Earnings
for the Calculation Year in question, assuming such interest compounded annually
during the period commencing with the first day of the calendar year immediately
succeeding the Base Year and ending on the last day of such Calculation Year.

          Section 1.14 Exercise Date. "Exercise Date" shall mean the date on
          --------------------------
which the Committee receives the written notice required under Section 3.4 of
this Agreement that Grantee has exercised the Option.

          Section 1.15 Fair Market Value. "Fair Market Value" of a share of
          ------------------------------
Stock on the Grant Date or Exercise Date, as the case may be, shall be
calculated in accordance with the Plan, in good faith in accordance with the
Code.

          Section 1.16 Grant Date. "Grant Date" shall mean March 1, 2001.
          -----------------------

          Section 1.17 Incentive Stock Option. "Incentive Stock Option" shall
          -----------------------------------
mean an option as defined in (S)422(b) of the Code.

          Section 1.18 Net Operating Income. "Net Operating Income" shall mean
          ---------------------------------
the dollar amount of net after tax operating income for a calendar year for
Mercantile-Safe Deposit and Trust Company, as reported to the Board and as may
be adjusted by the Committee in its discretion.

          Section 1.19 Net Operating Income AGR. "Net Operating Income AGR"
          -------------------------------------
shall mean the annual rate of growth in Net Operating Income, expressed as a
percentage (with any fraction of a percent of 0.50% or more being rounded up to
the nearest whole percent), determined in accordance with the following formula:

                                  (A-B)(100)
                                  ----------
                                       B

where "A" equals Net Operating Income for the Calculation Year, and "B" equals
Net

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Operating Income for the calendar year immediately preceding the Calculation
Year.

          Section 1.20 Net Operating Income CGR. "Net Operating Income CGR"
          -------------------------------------
shall mean the compounded growth rate of Net Operating Income, determined by
calculating the rate of interest at which Base Year Net Operating Income would
have to be invested to yield the Net Operating Income for the Calculation Year
in question, assuming such interest compounded annually during the period
commencing with the first day of the calendar year immediately succeeding the
Base Year and ending on the last day of such Calculation Year.

          Section 1.21 Normal Retirement Date. "Normal Retirement Date" shall
          -----------------------------------
mean the first day of the month coincident with or next following the date on
which Grantee attains age sixty-five (65).

          Section 1.22 Option. "Option" shall mean an option to acquire Stock
          -------------------
and, to the fullest extent permitted by the Code and other applicable law, shall
mean an Incentive Stock Option.

          Section 1.23 Option Amount. "Option Amount" shall mean 100,000 shares
          --------------------------
of Stock.

          Section 1.24 Option Price. "Option Price" shall mean the price per
          -------------------------
share of Stock at which the Option may be exercised.

          Section 1.25 Plan. "Plan" shall mean the Mercantile Bankshares
          -----------------
Corporation 1999 Omnibus Stock Plan.

          Section 1.26 Retirement. "Retirement" shall mean early or normal
          ------------------------
retirement in accordance with the terms of The Cash Balance Plan for Employees
of Mercantile Bankshares Corporation and Participating Affiliates, as it may
exist from time to time, or any successor plan.

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          Section 1.27 Stock. "Stock" shall mean shares of MBC's authorized but
          ------------------
unissued common stock.

                                   ARTICLE 2

                                GRANT OF OPTION

          Section 2.1 Grant of Option. On the Grant Date, MBC, pursuant to the
          ---------------------------
Plan, granted to Grantee an Option to purchase shares of Stock, not to exceed
the Option Amount, at an Option Price of $39.25 per share. To the fullest extent
permitted by the Code and other applicable law, the Option shall be an Incentive
Stock Option.

          Section 2.2 Term of Option. The Option granted pursuant to Section 2.1
          --------------------------
shall expire on February 28, 2011, unless and to the extent that the Option
terminates earlier pursuant to other provisions of this Agreement.

                                   ARTICLE 3

                     EXERCISE PROVISIONS AND RESTRICTIONS

          Section 3.1 Exercisability of Option or Portion of Option. The Option
          ---------------------------------------------------------
shall become exercisable, if at all, only on an Anniversary Date, except as
otherwise provided in Section 4.4 of this Agreement. The extent to which the
Option shall become exercisable on any Anniversary Date shall be determined
pursuant to the provisions of Sections 3.2 and 3.3 of this Agreement; provided
that, except as otherwise provided under Section 4.4 of this Agreement, in no
case shall the Option become exercisable on any one (1) Anniversary Date for
more than the Anniversary Date Option Amount. To the extent that, by application
of the provisions of Sections 3.2 or 3.3 of the Agreement, no portion of the
Option becomes exercisable on an Anniversary Date, or the Option becomes
exercisable for less than the Anniversary Date Option Amount on such Anniversary
Date, the Option shall terminate with respect to that number of shares of

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Stock that is equal to the difference between the Anniversary Date Option Amount
and the number of shares of Stock as to which the Option becomes exercisable on
such Anniversary Date.

          Section 3.2 Attainment of Earnings CGR. No portion of the Option shall
          --------------------------------------
become exercisable on an Anniversary Date unless the Earnings CGR for the
Calculation Year applicable to that Anniversary Date equals or exceeds five
percent (5%). If such Earnings CGR equals or exceeds five percent (5%), the
portion of the Anniversary Date Option Amount that shall become exercisable on
such Anniversary Date shall be determined pursuant to the provisions of Section
3.3 of this Agreement.

          Section 3.3 Determination of Exercisable Portion of Anniversary Date
          --------------------------------------------------------------------
Option Amount.
-------------

(a)  Amounts Dependent on Earnings. Subject to the provisions of the
     -----------------------------
first sentence of Section 3.2 of the Agreement, if the Earnings AGR for the
Calculation Year applicable to an Anniversary Date equals or exceeds six percent
(6%), Grantee may, on and after such Anniversary Date, exercise the Option with
respect to that percentage of the Anniversary Date Option Amount that
corresponds to the Earnings AGR in the following chart.

                                                Percentage of
                                           Anniversary Date Option
               Earnings AGR             Amount That May Be Exercised
               ------------             ----------------------------
                    6%                       10%
                    7%                       20%
                    8%                       30%
                    9%                       40%
                    10%                      50%

     (b)  Amounts Dependent on Net Operating Income. Subject to the provisions
          -----------------------------------------
of the first sentence of Section 3.2 of the Agreement, if, and only if, the Net
Operating

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Income CGR for the Calculation Year applicable to an Anniversary Date equals or
exceeds five percent (5%) and if the Net Operating Income AGR for such
Calculation Year equals or exceeds six percent (6%), Grantee may, on and after
such Anniversary Date, exercise the Option with respect to that percentage of
the Anniversary Date Option Amount that corresponds to the Net Operating Income
AGR in the following chart.

                                              Percentage of
                                           Anniversary Date Option
          Net Operating Income AGR       Amount That May Be Exercised
          ------------------------       ----------------------------

               6%                               10%
               7%                               20%
               8%                               30%
               9%                               40%
               10%                              50%

          Section 3.4 Manner of Exercise. The Option may be exercised, in whole
          ------------------------------
or in part, by delivering written notice to the Committee in such form as the
Committee may require from time to time. Such notice shall specify the number of
shares of Stock subject to the Option as to which the Option is being exercised,
and shall be accompanied by full payment of the Option Price of the shares of
Stock as to which the Option is being exercised. Payment of the Option Price may
be made either in cash or shares of Stock (including shares of Stock acquired
upon the exercise of an option) having a total Fair Market Value on the Exercise
Date equal to the Option Price multiplied by the number of shares of Stock as to
which the Option is being exercised. The Option may be exercised only in
multiples of whole shares and no partial shares shall be issued. The minimum
number of shares of Stock for which the Option may be exercised shall be the
lesser of one hundred (100) shares or the entire number of shares for which the
Option is exercisable on the Exercise Date. If, as of the fourth Anniversary
Date, the total number of shares as to which the Option is exercisable

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includes a partial share, the Option for such partial share, whether or not
previously designated by the Committee as an Incentive Stock Option, shall be
deemed to be a non- Incentive Stock Option. On the first date, on or after the
fourth Anniversary Date, that the Fair Market Value of a share of Stock equals
or exceeds the Option Price, Grantee shall be deemed to have simultaneously
exercised the Option for such partial share and to have sold same to MBC for
such Fair Market Value. MBC shall remit to Grantee, in payment of the purchase
price of such partial share, the excess, if any, of the Fair Market Value of
such partial share over the Option Price.

          Section 3.5 Issuance of Shares and Payment of Cash upon Exercise. Upon
          ----------------------------------------------------------------
exercise of the Option, in whole or in part, in accordance with the terms of the
Agreement, and upon payment of the Option Price for the shares of Stock as to
which the Option is exercised, MBC shall issue to Grantee the number of shares
of Stock so paid for, in the form of fully paid and non-assessable Stock.

          Section 3.6 Loan or Guaranty. Solely at the discretion of the
          ----------------------------
Committee, and upon Grantee's written request, MBC may, but shall not be
required to, assist Grantee in the exercise of the Option by making a loan to
Grantee or by guaranteeing a third- party loan to Grantee. Such a loan or
guaranty shall be conditioned upon prior receipt by the Committee of
satisfactory assurances of Grantee's net worth and repayment ability. Subject to
Regulation U of the Federal Reserve Board, any such loan or guaranty may be in
an amount up to one hundred percent (100%) of the Option Price of the shares of
Stock as to which the Option is being exercised. All loans shall bear interest
at a rate determined by the Committee based upon loans of similar maturity, but
in no event shall the interest rate be less than the rate necessary to avoid the
imputation of interest or original issue discount under the provisions of the
Code. All other terms
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of any loan or guaranty (including terms of repayment) shall be established by
the Committee, subject to Regulation U of the Federal Reserve Board and all
other applicable federal and state laws and regulations.

                                   ARTICLE 4

                             TERMINATION OF OPTION

          Section 4.1 Termination of Employment For Reason Other Than Death,
          ------------------------------------------------------------------
Disability, or Retirement. The Option granted to Grantee shall terminate with
-------------------------
respect to any shares of Stock as to which the Option has not been exercised as
of the date Grantee is no longer employed by either MBC or an Affiliate for any
reason other than Grantee's death, Disability or Retirement, whether or not the
Option was exercisable on such date.

          Section 4.2 Upon Grantee's Death. In the event that upon Grantee's
          --------------------------------
date of death any portion of the Option is exercisable, then Grantee's executor,
personal representative or the person to whom the Option shall have been
transferred by will or the laws of descent and distribution, as the case may be,
may exercise all or any part of the portion of the Option exercisable as of the
date of death, provided such exercise occurs within twelve (12) months after the
date Grantee dies, but not later than the end of the stated term of the Option.
Upon Grantee's death, the portion of the Option, if any, that has not become
exercisable as of the date of Grantee's death shall terminate on the date of
Grantee's death.

          Section 4.3 Termination of Employment By Reason of Disability. In the
          -------------------------------------------------------------
event that Grantee ceases to be an employee of MBC or an Affiliate by reason of
Disability, the portion of the Option, if any, that has become exercisable as of
the date of Disability may be exercised in whole or in part at any time on or
after the date of Disability, but

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not later than the end of the stated term of the Option or as otherwise provided
by the provisions of Section 4.2 of the Agreement. Upon Grantee's termination of
employment by reason of Disability, the portion of the Option, if any, that has
not become exercisable as of the date of Disability shall terminate on the date
of Disability.

          Section 4.4 Termination of Employment By Reason of Retirement.
          -------------------------------------------------------------

          (a)  Early Retirement.
               ----------------

               (i)  Exercisable Portion of Option. In the event that Grantee
                    -----------------------------
ceases to be an employee of MBC or an Affiliate by reason of Retirement at any
time prior to Grantee's Normal Retirement Date, the portion of the Option, if
any, that has become exercisable as of the date of Retirement may be exercised
in whole or in part at any time on or after the date of Retirement, but not
later than the end of the stated term of the Option or as otherwise provided by
the provisions of Section 4.2 of this Agreement.

               (ii) Non-exercisable Portion of Option. In the event that Grantee
                    ---------------------------------
ceases to be an employee of MBC or an Affiliate by reason of Retirement at any
time prior to Grantee's Normal Retirement Date, the portion of the Option, if
any, that has not become exercisable as of the date of Retirement shall
terminate on the date of Retirement.

          (b)  Normal Retirement.
               -----------------

               (i)  Exercisable Portion of Option. In the event that Grantee
                    -----------------------------
ceases to be an employee of MBC or an Affiliate by reason of Retirement on or
after Grantee's Normal Retirement Date, the portion of the Option, if any, that
has become exercisable as of the date of Retirement may be exercised in whole or
in part at any time on or after the date of Retirement, but not later than the
end of the stated term of the Option or as otherwise provided by the provisions
of Section 4.2 of this Agreement.

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               (ii) Non-exercisable Portion of Option. In the event that upon
                    ---------------------------------
the occurrence of Grantee's Retirement on or after Grantee's Normal Retirement
Date all or a portion of the Option has not become exercisable solely because
one (1) or more of the first four (4) Anniversary Dates have not occurred
(hereinafter referred to as the "Remaining Portion"), then such Remaining
Portion shall become exercisable, if at all, on the later of the occurrence of
Grantee's Retirement or March 1 of the calendar year in which such retirement
occurs. The Remaining Portion shall not include any portion of the Option that
has terminated pursuant to the provisions of Sections 3.1, 3.2, 3.3, 4.1, 4.2 or
4.3 of this Agreement. The extent to which the Remaining Portion shall become
exercisable shall be determined pursuant to the provisions of Sections 3.2 and
3.3 of this Agreement; provided, however, for purposes of such Sections, that
the term "Remaining Portion" shall be substituted for the term "Anniversary Date
Option Amount", the "Calculation Year" shall be the calendar year ending
immediately prior to the calendar year in which Grantee's Retirement occurs, and
the date of Grantee's Retirement shall be substituted for "Anniversary Date" if
the date of such Retirement occurs after March 1 of the calendar year in which
such Retirement occurs. The amount, if any, of the Remaining Portion of the
Option that becomes so exercisable may be exercised in whole or in part at any
time, but not later than the end of the stated term of the Option or as
otherwise provided by the provisions of Section 4.2 of this Agreement.

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                                   ARTICLE 5

                                 MISCELLANEOUS

          Section 5.1 Non-Guarantee of Employment. Nothing in the Plan or this
          ---------------------------------------
Agreement shall be construed as a contract of employment between MBC (or an
Affiliate) and Grantee, or as a contractual right of Grantee to continue in the
employ of MBC or an Affiliate, or as a limitation of the right of MBC or an
Affiliate to discharge Grantee at any time.

          Section 5.2 No Rights of Stockholder. Grantee shall not have any of
          -------------------------------------
the rights of a stockholder with respect to the shares of Stock that may be
issued upon the exercise of the Option until such shares of Stock have been
issued to him upon the due exercise of the Option.

          Section 5.3 Notice of Disqualifying Disposition. If Grantee makes a
          -----------------------------------------------
disposition (as that term is defined in (S)424(c) of the Code) of any shares of
Stock acquired pursuant to the exercise of an Incentive Stock Option within two
(2) years of the Grant Date or within one (1) year after the shares of Stock are
transferred to Grantee, Grantee shall notify the Committee of such disposition
in writing.

          Section 5.4 Withholding Taxes. MBC or any Affiliate shall have the
          -----------------------------
right to deduct from any compensation or any other payment of any kind
(including withholding the issuance of shares of Stock) due Grantee the amount
of any federal, state or local taxes required by law to be withheld as the
result of the exercise of the Option or the disposition (as that term is defined
in (S)424(c) of the Code) of shares of Stock acquired pursuant to the exercise
of the Option. In lieu of such deduction, MBC may require Grantee to make a cash
payment to MBC or an Affiliate equal to the amount required to be withheld. If
Grantee does not make such payment when requested, MBC may

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refuse to issue any Stock certificate under the Plan until arrangements
satisfactory to the Committee for such payment have been made.

          Section 5.5 Nontransferability of Option. Except as otherwise
          ----------------------------------------
determined by the Committee, the Option shall be nontransferable otherwise than
by will or the laws of descent and distribution, and during the lifetime of
Grantee, the Option may be exercised only by Grantee or, during the period
Grantee is under a legal disability, by Grantee's guardian or legal
representative.

          Section 5.6 Agreement Subject to Charter and By-Laws. This Agreement
          ----------------------------------------------------
is subject to the Charter and By-Laws of MBC, and any applicable federal or
state laws, rules or regulations.

          Section 5.7 Gender. As used herein the masculine shall include the
          -------------------
feminine as the circumstances may require.

          Section 5.8 Headings. The headings in this Agreement are for reference
          --------------------
purposes only and shall not affect the meaning or interpretation of this
Agreement.

          Section 5.9 Notices. All notices and other communications made or
          -------------------
given  pursuant to this Agreement shall be in writing and shall be sufficiently
made or given if hand delivered or mailed by certified mail, addressed to
Grantee at the address contained in the records of MBC or an Affiliate, or to
MBC for the attention of its Secretary at its principal office.

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                                  ARTICLE 6

                              SCOPE OF AGREEMENT

          Section 6.1 Entire Agreement; Modification. This Agreement contains
          ------------------------------------------
the entire agreement between the parties with respect to the subject matter
contained herein and shall be binding upon MBC, its successors and assigns and
upon the Grantee and Grantees' heirs, personal representatives and assigns. This
Agreement may be modified by the Committee as permitted by the Plan, including
modification under Section 9.3 thereof and any modification to comply with the
Code or to cure any ambiguity or to correct or supplement any provision which
may be inconsistent with any other provision or which may be otherwise
defective.

          Section 6.2 Counterparts. This Agreement may be executed
          ------------------------
simultaneously in one or more counterparts, each of which shall be deemed to be
an original and all of which together shall constitute one and the same
instrument. Signatures evidencing execution of this Agreement on behalf of
Mercantile Bankshares Corporation may be in facsimile or photocopy form.

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     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

ATTEST:                                 MERCANTILE BANKSHARES CORPORATION

/s/ Alan D. Yarbro                      By:      /s/ Jack E. Steil
--------------------------------           --------------------------------
Alan D. Yarbro                                   Jack E. Steil
Secretary                                        Executive Vice President


WITNESS:                                GRANTEE


  /s/ Alan D. Yarbro                      /s/ Edward J. Kelly, III
--------------------------------        -----------------------------------
                                        Edward J. Kelly, III

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