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                                                       Exhibit 10.11


                 FIRST AMENDMENT TO MASTER LOAN AGREEMENT


     THIS FIRST AMENDMENT TO MASTER LOAN AGREEMENT (this "Amendment"),
effective as of September 30, 1997, by and among INTERSTATE GENERAL COMPANY
L.P., a Delaware limited partnership ("IGC"), and AMERICAN COMMUNITY
PROPERTIES TRUST, a Maryland real estate investment trust ("ACPT") (IGC and
ACPT are collectively herein the "Borrower"), ST. CHARLES COMMUNITY, LLC, a
Delaware limited liability company ("Property Owner"), and BANC ONE CAPITAL
PARTNERS, IV, LTD, an Ohio limited liability company (the "Lender");
WITNESSETH:

                                 RECITALS

     WHEREAS, effective on or about August 1, 1997, the Borrower, Property
Owner, and Lender entered into that certain Master Loan Agreement (the
"Loan Agreement") whereby, among other things, Lender agreed to provide
financing to Borrower in the principal amount of up to Twenty Million
Dollars ($20,000,000.00), and Property Owner guaranteed such obligations of
Borrower and granted to Lender a first lien on certain real property owned
by Property Owner, all as more fully set forth in the Loan Agreement and
the documents executed in connection therewith; and

     WHEREAS, in September, 1995, James J. Wilson ("Wilson") IGC and St.
Charles Associates, L.P., a Delaware limited partnership ("SCA"), were
indicted by the United States District Court for the District of Maryland
for four (4) felony and four (4) misdemeanor violations of the Clean Water
Act, 33 U.S.C. Section 1311(a) (collectively the "Criminal Actions"); and

     WHEREAS, on February 29, 1996, a jury convicted Wilson, IGC and SCA of
the aforementioned felony charges; and

     WHEREAS, as a result thereof, inter alia, IGC was fined Two Million
Dollars ($2,000,000.00) and SCA was fined One Million Dollars
($1,000,000.00) and each of IGC and SCA was placed on probation for five
(5) years in order to implement a wetlands restoration mitigation plan
proposed by the United States government; and

     WHEREAS, IGC and SCA  have appealed the convictions and the
accompanying punishments to the United States Court of Appeals for the
Fourth Circuit.

     WHEREAS, the Borrower, Property Owner and Lender anticipated that the
Fourth Circuit would rule on IGC's and SCA's appeal of the Criminal Action
on or before September 30, 1997; and

     WHEREAS, pursuant to Section 5.2 of the Loan Agreement, upon the
earlier of September 30, 1997 or a determination by the United States Court
of Appeals for the Fourth Circuit regarding the Criminal Action, the
Borrower was to provide Lender with a management succession plan.  If a
decision rendered by the United States Court of Appeals for the Fourth
Circuit was unfavorable to IGC, or if a decision was not rendered on or
before September 30, 1997, then IGC was required to demand the resignation
of Wilson as an officer and Chairman of the Board of Directors of IGC or
any successor company; and


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     WHEREAS, the Borrower and Property Owner have requested, and Lender
has agreed, pursuant to the terms hereof, to extend the time deadline for
resolution of the appeal of the Criminal Action and/or the removal of
Wilson as an officer and Chairman of the Board of Directors of the managing
general partner of IGC, and to reestablish the outside date thereof to be
the earlier of March 31, 1998, the decision of the Fourth Circuit
unfavorable to IGC concerning the appeal of the Criminal Action or the
Restructuring (as defined in the Loan Agreement).

     NOW, THEREFORE, for consideration of the aforementioned premises, and
such other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the Borrower, Property Owner, and Lender
hereby agree as follows:

     1.   Section 5.22 of the Loan Agreement entitled, "Resolution of
Pending Litigation" shall be deleted in its entirety and replaced as
follows:

          "5.22.    Resolution of Pending Litigation.  Upon the earlier of
     (i) March 31, 1998, (ii) determination by the United States Court of
     Appeals for the Fourth Circuit regarding the Criminal Action, or (iii)
     the Restructuring, provide Lender with a management succession plan. 
     If the decision rendered by the United States Court of Appeals for the
     Fourth Circuit is unfavorable to IGC, or if a decision is not rendered
     on or before March 31, 1998, then IGC shall demand the resignation of
     James J. Wilson as an officer and Chairman of the Board of Directors
     of the managing general partner of IGC, or any successor company. 
     Notwithstanding the foregoing, following the Restructuring, James J.
     Wilson may continue or resume his position as an officer and Chairman
     of the Board of Directors of the managing general partner of IGC.

     2.   Except as herein provided above, the Loan Agreement shall remain
unmodified and in full force and effect, as if this Amendment had not been
made.

     3.   This Amendment may be executed in two or more counterparts, each
of which shall be deemed an original and all of which, when taken together,
shall constitute one and the same document.

     4.   All costs incurred by Lender in conjunction with the preparation
and execution of this Amendment and the First Amendment to Guaranty
Agreement between Lender and Wilson, including legal fees, shall be paid by
the Borrower.

     IN WITNESS WHEREOF, each of the parties hereto have executed and
delivered this Agreement under their respective seals as of the day and
year first written above.

                                   INTERSTATE GENERAL COMPANY LP
WITNESS:
                                   By:  INTERSTATE GENERAL MANAGEMENT
                                        CORPORATION, a Delaware corporation

/s/ Martha Haupt                    By: /s/ James Michael Wilson
-------------------------               -----------------------------(SEAL)
                                        Name:  James Michael Wilson
                                        Title: Chief Financial Officer


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                                   AMERICAN COMMUNITY PROPERTIES TRUST

/s/ Martha Haupt                   By:  /s/ Edwin L. Kelly
-------------------------               -----------------------------(SEAL)
                                        Name:  Edwin L. Kelly
                                        Title: Managing Trustee


                                   ST. CHARLES COMMUNITY, LLC

/s/ Martha Haupt                   By:  /s/ Edwin L. Kelly
-------------------------               -----------------------------(SEAL)
                                        Name:  Edwin L. Kelly
                                        Title: Management Committee Chair


                                   BANC ONE CAPITAL PARTNERS IV, LTD.

                                   By:  BOCP Holdings Corporation, its
                                        Manager

                                    By: /s/ Michael S. Wood
-------------------------               -----------------------------(SEAL)
                                        Name:  Michael S. Wood
                                        Title: Authorized Signer