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                                                                    Exhibit 10.2


                         INTERNATIONAL STEEL GROUP INC.

                               FOURTH AMENDMENT TO
                          CREDIT AND GUARANTY AGREEMENT

            This FOURTH AMENDMENT TO CREDIT AND GUARANTY AGREEMENT, dated as of
April 27, 2004 (this "AMENDMENT"), is entered into by and among INTERNATIONAL
STEEL GROUP INC., a Delaware corporation (the "COMPANY"), ISG ACQUISITION INC.,
ISG CLEVELAND INC., ISG HENNEPIN INC., ISG INDIANA HARBOR INC., ISG WARREN INC.,
ISG RIVERDALE INC., ISG PLATE LLC (F/K/A ISG PLATE INC.), ISG PIEDMONT LLC
(F/K/A ISG PIEDMONT INC.), ISG BURNS HARBOR LLC (F/K/A ISG BURNS HARBOR INC.),
ISG SPARROWS POINT LLC (F/K/A ISG SPARROWS POINT INC.), ISG STEELTON LLC (F/K/A
ISG STEELTON INC.), and ISG LACKAWANNA LLC (F/K/A ISG LACKAWANNA INC.) (each a
"BORROWER" and collectively, the "BORROWERS"), the CREDIT SUPPORT PARTIES listed
on the signature pages hereto, the Lenders listed on the signature pages hereto,
UBS AG, STAMFORD BRANCH, as Administrative Agent (together with its permitted
successors in such capacity, "ADMINISTRATIVE AGENT"), GOLDMAN SACHS CREDIT
PARTNERS L.P., as Syndication Agent (in such capacity, "SYNDICATION AGENT"), THE
CIT GROUP/BUSINESS CREDIT, INC., as Collateral Agent (together with its
permitted successor in such capacity, "COLLATERAL AGENT"), FLEET CAPITAL
CORPORATION, as Co-Documentation Agent and LASALLE BANK NATIONAL ASSOCIATION, as
Co-Documentation Agent, and is made with reference to that certain Credit and
Guaranty Agreement, dated as of May 7, 2003 (as amended through the date hereof,
the "CREDIT AGREEMENT"). Capitalized terms used herein not otherwise defined
herein or otherwise amended hereby shall have the meanings ascribed thereto in
the Credit Agreement.

                                    RECITALS:

            WHEREAS, the Company and the Borrowers have requested that the
Lenders agree to make amendments to certain provisions of the Credit Agreement;

            WHEREAS, the Lenders have agreed to amend certain provisions of the
Credit Agreement, in each case in the manner, and on the terms and conditions,
provided for herein.

            NOW, THEREFORE, in consideration of the premises and the agreements,
provisions and covenants herein contained, the parties hereto agree as follows:

SECTION I. AMENDMENTS TO CREDIT AGREEMENT

      Upon satisfaction of the conditions set forth in Section II herein, the
Credit Agreement shall be amended as follows in this Section I:

      A. AMENDMENTS TO SECTION 1: DEFINITIONS

            Section 1.1 of the Credit Agreement is hereby amended by adding the
following definitions in proper alphabetical sequence:
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                  "'FOURTH AMENDMENT' means that certain Fourth Amendment to
      Credit and Guaranty Agreement dated as of April 27, 2004, among the
      Company, Borrowers, Administrative Agent, Syndication Agent, Collateral
      Agent, Documentation Agent and the financial institutions and the Credit
      Support Parties listed on the signature pages thereto."

                  "'FOURTH AMENDMENT EFFECTIVE DATE' means the Fourth Amendment
      Effective Date, as defined in the Fourth Amendment."

      B. AMENDMENTS TO SECTION 5: AFFIRMATIVE COVENANTS

                  (i) Section 5 of the Credit Agreement is hereby amended by
      adding the following sentence at the conclusion of Section 5.1(a):

                  "notwithstanding any of the foregoing to the contrary, the
      Company shall not be required to (i) deliver the Financial Officer
      Certification required in clause (z) above for any period ending prior to
      the Fourth Amendment Effective Date or (ii) deliver Monthly Financial
      Statements for the month of December, 2003 or for the month of December in
      any succeeding Fiscal Year;"

                  (ii) Section 5 of the Credit Agreement is hereby further
      amended by deleting the references to "Section 6.7" in clause (ii) of
      Section 5.1(c) and replacing them with "Section 6.8".

                  (iii) Section 5 of the Credit Agreement is hereby further
      amended by adding the following sentence at the conclusion of Section
      5.1(j):

                  "; provided that with respect to the Fiscal Year ending 2003,
      Company shall be required to deliver such report on or before April 29,
      2004;"

SECTION II. CONDITIONS PRECEDENT TO EFFECTIVENESS

            The amendments set forth in Section I hereof shall be effective on
and as of the date hereof (the "FOURTH AMENDMENT EFFECTIVE DATE") upon the
satisfaction, or waiver by the Requisite Lenders, on or after the date hereof,
of the following conditions:

                  (i) The Company, the Borrowers, the other Credit Parties and
      the Requisite Lenders shall have indicated their consent by the execution
      and delivery of the signature pages hereof to the Administrative Agent.

                  (ii) The Administrative Agent shall have received a
      certificate from the Company, certifying that as of the Fourth Amendment
      Effective Date, the representations and warranties contained in Section
      III herein and in the other Credit Documents are true and correct in all
      material respects on and as of the Fourth Amendment Effective Date to the
      same extent as though made on and as of the Fourth Amendment Effective
      Date, except to the extent such representations and warranties
      specifically relate to an earlier


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      date, in which case such representations and warranties are true and
      correct in all material respects on and as of such earlier date.

                  (iii) The Administrative Agent shall have received a
      certificate from the Company, certifying that as of the Fourth Amendment
      Effective Date (after giving effect to the amendments contained herein),
      no event shall have occurred and be continuing that would constitute an
      Event of Default or a Default.

                  (iv) The Administrative Agent and Lenders shall have received
      such other documents and information regarding Credit Parties and the
      Credit Agreement as the Administrative Agent or Lenders may have
      reasonably requested prior to the date hereof.

SECTION III. REPRESENTATIONS AND WARRANTIES

      A. CORPORATE POWER AND AUTHORITY. Each Credit Party has all requisite
corporate power and authority to enter into this Amendment and to carry out the
transactions contemplated by, and perform its obligations under, this Amendment.

      B. AUTHORIZATION OF AGREEMENTS. The execution and delivery of this
Amendment has been duly authorized by all necessary corporate or partnership (as
applicable) action on the part of each Credit Party.

      C. BINDING OBLIGATION. This Amendment has been duly executed and delivered
by each Credit Party and constitutes a legal, valid and binding obligation of
each Credit Party enforceable against each Credit Party in accordance with its
terms, except as enforceability may be limited by bankruptcy, insolvency,
moratorium, reorganization or other similar laws affecting creditors' rights
generally and except as enforceability may be limited by general principles of
equity (regardless of whether such enforceability is considered in a proceeding
in equity or at law).

      D. INCORPORATION OF REPRESENTATIONS AND WARRANTIES FROM CREDIT DOCUMENTS.
The representations and warranties contained in the Credit Documents are and
will be true and correct in all material respects on and as of the Fourth
Amendment Effective Date (after giving effect to the amendments and waivers
contained herein) to the same extent as though made on and as of that date,
except to the extent such representations and warranties specifically relate to
an earlier date, in which case they were true and correct in all material
respects on and as of such earlier date.

      E. ABSENCE OF DEFAULT. No event has occurred and is continuing (after
giving effect to the amendments and waivers contained herein) or will result
from the consummation of the transactions contemplated by this Amendment that
would constitute an Event of Default or a Default.

SECTION IV. ACKNOWLEDGMENT AND CONSENT


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            Each of the Company, each wholly-owned Domestic Subsidiary of the
Company (other than the Borrowers and the Specified Subsidiaries) and ISG Real
Estate Inc. has (i) guaranteed the Obligations and (ii) (other than ISG Real
Estate Inc.) created Liens in favor of Lenders on the Collateral to secure the
Obligations subject to the terms and provisions of the Credit Agreement. Each of
the Company, ISG Real Estate Inc., and each wholly-owned Domestic Subsidiary of
the Company who has guaranteed the Obligations are collectively referred to
herein as the "CREDIT SUPPORT PARTIES", and the Credit Agreement and the
Collateral Documents are collectively referred to herein as the "CREDIT SUPPORT
DOCUMENTS".

            Each Credit Support Party hereby acknowledges that it has reviewed
the terms and provisions of the Credit Agreement and this Amendment and consents
to the amendment of the Credit Agreement effected pursuant to this Amendment.
Each Credit Support Party hereby confirms that each Credit Support Document to
which it is a party or otherwise bound and all Collateral encumbered thereby
will continue to guarantee or secure, as the case may be, to the fullest extent
possible in accordance with and subject to the Credit Support Documents the
payment and performance of all "Obligations" under each of the Credit Support
Documents, as the case may be (in each case as such terms are defined in the
applicable Credit Support Document), including without limitation the payment
and performance of all such "Obligations" under each of the Credit Support
Documents, as the case may be, in respect of the Obligations of the Company now
or hereafter existing under or in respect of the Credit Agreement and hereby
pledges and assigns to the Collateral Agent, and grants to the Collateral Agent
a continuing lien on and security interest in and to all Collateral as
collateral security for the prompt payment and performance in full when due of
the "Obligations" under each of, and in accordance with and subject to, the
Credit Support Documents to which it is a party (whether at stated maturity, by
acceleration or otherwise).

            Each Credit Support Party acknowledges and agrees that all of the
Credit Support Documents to which it is a party or otherwise bound shall
continue in full force and effect and that all of its obligations thereunder
shall be valid and enforceable and shall not be impaired or limited by the
execution or effectiveness of this Amendment. Each Credit Support Party
represents and warrants that all representations and warranties contained in the
Credit Agreement, this Amendment and the Credit Support Documents to which it is
a party or otherwise bound are true and correct in all material respects on and
as of the Fourth Amendment Effective Date to the same extent as though made on
and as of the Fourth Amendment Effective Date, except to the extent such
representations and warranties specifically relate to an earlier date, in which
case they were true, correct and complete in all material respects on and as of
such earlier date.

            Each Credit Support Party acknowledges and agrees that (i)
notwithstanding the conditions to effectiveness set forth in this Amendment,
such Credit Support Party (other than the Company) is not required by the terms
of the Credit Agreement or any other Credit Document to consent to the
amendments to the Credit Agreement effected pursuant to this Amendment and (ii)
nothing in the Credit Agreement, this Amendment or any other Credit Document
shall be deemed to require the consent of such Credit Support Party (other than
the Company) to any future amendments to the Credit Agreement.


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SECTION V. MISCELLANEOUS

      A. BINDING EFFECT. This Amendment shall be binding upon the parties hereto
and their respective successors and assigns and shall inure to the benefit of
the parties hereto and the successors and assigns of Lenders. No Credit Party's
rights or obligations hereunder or any interest therein may be assigned or
delegated by any Credit Party without the prior written consent of all Lenders.

      B. SEVERABILITY. In case any provision in or obligation hereunder shall be
invalid, illegal or unenforceable in any jurisdiction, the validity, legality
and enforceability of the remaining provisions or obligations, or of such
provision or obligation in any other jurisdiction, shall not in any way be
affected or impaired thereby.

      C. REFERENCE TO CREDIT AGREEMENT. On and after the Fourth Amendment
Effective Date, each reference in the Credit Agreement to "this Agreement",
"hereunder", "hereof", "herein" or words of like import referring to the Credit
Agreement, and each reference in the other Credit Documents to the "Credit
Agreement", "thereunder", "thereof" or words of like import referring to the
Credit Agreement shall mean and be a reference to the Credit Agreement as
amended by this Amendment.

      D. EFFECT ON CREDIT AGREEMENT. Except as specifically amended by this
Amendment, the Credit Agreement and the other Credit Documents shall remain in
full force and effect and are hereby ratified and confirmed.

      E. EXECUTION. The execution, delivery and performance of this Amendment
shall not, except as expressly provided herein, constitute a waiver of any
provision of, or operate as a waiver of any right, power or remedy of any Agent
or Lender under, the Credit Agreement or any of the other Credit Documents.

      F. HEADINGS. Section headings herein are included herein for convenience
of reference only and shall not constitute a part hereof for any other purpose
or be given any substantive effect.

      G. APPLICABLE LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE
PARTIES HEREUNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN
ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

      H. COUNTERPARTS. This Amendment may be executed in any number of
counterparts, each of which when so executed and delivered shall be deemed an
original, but all such counterparts together shall constitute but one and the
same instrument. As set forth herein, this Amendment shall become effective upon
the execution of a counterpart hereof by each of the parties hereto and receipt
by the Administrative Agent and the Syndication Agent of written or telephonic
notification of such execution and authorization of delivery thereof.


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            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be duly executed and delivered by their respective officers thereunto duly
authorized as of the date first written above.

COMPANY                          INTERNATIONAL STEEL GROUP INC.


                                 By: /s/ Rodney Mott
                                     ------------------------------------
                                     Name: Rodney Mott
                                     Title: Chief Executive Officer

BORROWERS                        ISG ACQUISITION INC.
                                 ISG CLEVELAND INC.
                                 ISG HENNEPIN INC.
                                 ISG INDIANA HARBOR INC.
                                 ISG WARREN INC.
                                 ISG RIVERDALE INC.
                                 ISG PLATE LLC
                                 ISG PIEDMONT LLC
                                 ISG BURNS HARBOR LLC
                                 ISG SPARROWS POINT LLC
                                 ISG STEELTON LLC
                                 ISG LACKAWANNA LLC


                                 By: /s/ Rodney Mott
                                     ------------------------------------
                                     Name: Rodney Mott
                                     Title: Chief Executive Officer
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CREDIT SUPPORT PARTIES

                                 ISG RAILWAYS INC.
                                 ISG/EGL HOLDING COMPANY
                                 ISG CLEVELAND WORKS RAILWAY COMPANY
                                 ISG SOUTH CHICAGO & INDIANA HARBOR RAILWAY
                                 COMPANY
                                 ISG VENTURE INC.
                                 ISG SALES INC.
                                 ISG CLEVELAND WEST INC.
                                 ISG CLEVELAND WEST PROPERTIES INC.
                                 ISG TECHNOLOGIES INC.
                                 ISG REAL ESTATE INC.
                                 ISG HIBBING INC.
                                 HIBBING TACONITE HOLDING INC.
                                 ISG PLATE SERVICES LLC
                                 ISG SPARROWS POINT SERVICES LLC
                                 ISG BURNS HARBOR SERVICES LLC
                                 ISG LACKAWANNA SERVICES LLC
                                 ISG STEELTON SERVICES LLC
                                 ISG CHICAGO COLD ROLLING LLC


                                 By: /s/ Rodney Mott
                                     ------------------------------------
                                     Name: Rodney Mott
                                     Title: President
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ADMINISTRATIVE AGENT AND ISSUING BANK    UBS AG, STAMFORD BRANCH


                                         By: /s/ Wilfred V. Saint
                                             -----------------------------------
                                             Name: Wilfred V. Saint
                                             Title: Director
                                                    Banking Product Services, US


                                         By: /s/ Juan Zuniga
                                             -----------------------------------
                                             Name: Juan Zuniga
                                             Title: Associate Director
                                                    Banking Product Services, US



LENDER AND SWING LINE LENDER             UBS AG, CAYMAN ISLANDS BRANCH


                                         By: /s/ Wilfred V. Saint
                                             -----------------------------------
                                             Name: Wilfred V. Saint
                                             Title: Director
                                                    Banking Product Services, US


                                         By: /s/ Juan Zuniga
                                             -----------------------------------
                                             Name: Juan Zuniga
                                             Title: Associate Director
                                                    Banking Product Services, US


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JOINT LEAD ARRANGER, JOINT
BOOKRUNNER, SYNDICATION AGENT
AND A LENDER                             GOLDMAN SACHS CREDIT PARTNERS L.P.


                                         By: /s/ Elizabeth Fischer
                                             -----------------------------------
                                             Name: Elizabeth Fischer
                                             Title: Authorized Signatory
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COLLATERAL AGENT
AND A LENDER                             THE CIT GROUP/BUSINESS CREDIT, INC.


                                         By: /s/ George Louis McKinley
                                             --------------------------------
                                             Name: George Louis McKinley
                                             Title: Vice President
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CO-DOCUMENTATION AGENT
AND A LENDER                             FLEET CAPITAL CORPORATION


                                         By: /s/ Michael Kerneklian
                                             -------------------------------
                                             Name: Michael Kerneklian
                                             Title: Vice President
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CO-DOCUMENTATION AGENT
AND A LENDER                             LASALLE BANK NATIONAL ASSOCIATION


                                         By: /s/ Keith J. Cable
                                             --------------------------------
                                             Name: Keith J. Cable
                                             Title: Vice President