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                                                                     EXHIBIT 5.1


                   [Goodwin, Procter & Hoar  LLP Letterhead]


    
                              February 24, 1999     


Maryland Property Capital Trust, Inc.
177 Milk Street
Boston, MA 02109


     Re:  Legality of Securities to be Registered
          under Registration Statement on Form S-4
          ----------------------------------------

Ladies and Gentlemen:

     This opinion is furnished in connection with the registration on Form S-4
(the "Registration Statement") pursuant to the Securities Act of 1933, as
amended (the "Securities Act"), of 159,737 shares of common stock, par value
$.01 per share, of Maryland Property Capital Trust, Inc., a Maryland corporation
(the "Corporation"), which will be issued to the shareholders of Property
Capital Trust (the "Trust") in connection with the Merger (as defined below).

     We have acted as counsel to the Corporation in connection with the
preparation and filing with the Securities and Exchange Commission of the
Registration Statement and the proposed merger (the "Merger") of the Trust into
the Corporation pursuant to the Agreement and Plan of Merger, by and between the
Corporation and the Trust, dated as of June 18, 1998, as amended (the "Merger
Agreement").
    
     In connection with rendering this opinion, we have examined the Articles of
Amendment and Restatement of the Corporation, as approved by the Board of
Directors of the Corporation and as expected to be filed with the Secretary of
State of the State of Maryland following approval by the Trust's shareholders of
the Merger and approval by the Trust as the sole shareholder of the Corporation,
which authorizes, among other things, the increase in the number of authorized
shares of the common stock of the Corporation from 100 to 10,000,000, the Bylaws
of the Corporation, such records of the corporate proceedings of the Corporation
as we deemed material, the Registration Statement and the exhibits thereto, and
such other certificates, receipts, records and documents as we considered
necessary for the purposes of this opinion. In our examination, we have assumed
the genuineness of all signatures, the legal capacity of natural persons, the
authenticity of all documents submitted to us as certified, photostatic or
facsimile copies, the authenticity of the originals of such copies and the
authenticity of telephonic confirmations of public officials and others. As to
facts material to our opinion, we have relied upon certificates or telephonic
confirmations of public officials and certificates, documents, statements and
other information of the Corporation or representatives or officers thereof.    
    
     We express no opinion concerning the laws of any jurisdictions other than
the laws of the United States of America and the Maryland General Corporation
Law as in effect on the date hereof.     

     Based upon the foregoing, we are of the opinion that under the Maryland
General Corporation Law, pursuant to which the Corporation is incorporated, the
shares to be issued to the shareholders of the Trust in 

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Maryland Property Capital Trust, Inc.
February 24, 1999
Page 2

connection with the Merger, when issued in accordance with the terms described
in the Merger Agreement, will be duly authorized, validly issued, fully paid and
nonassessable.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to us with respect to this opinion
under the heading "Legal Matters" in the Prospectus which is a part of such
Registration Statement.


                                Very truly yours,

                                /s/ Goodwin, Procter & Hoar  LLP

                                GOODWIN, PROCTER & HOAR  LLP