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                                                               Exhibit 4.2

                         CROWN CENTRAL PETROLEUM CORPORATION

                                     and

                           FIRST UNION NATIONAL BANK,
                                 Rights Agent


                       FIRST AMENDMENT TO RIGHTS AGREEMENT


Dated as of April 10, 2000

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                   FIRST AMENDMENT TO RIGHTS AGREEMENT

     THIS FIRST AMENDMENT TO RIGHTS AGREEMENT (this "First Amendment") is
entered into as of the 10th day of April, 2000, by and between Crown
Central Petroleum Corporation, a Maryland corporation (the "Company"), and
First Union National Bank, a national banking association, as rights agent
(the "Rights Agent"), and amends that certain Rights Agreement dated as of
February 1, 2000 by and between the Company and the Rights Agent (the
"Rights Agreement").

                               RECITALS

     A.     On February 1, 2000, in order to preserve for stockholders the
long-term value of the Company, the Board of Directors of the Company
adopted resolutions authorizing, among other things, (i) a dividend with
respect to shares of common stock of the Company outstanding on February
15, 2000 of one Series A Preferred share purchase right (a "Series A
Right") for each share of Class A Common and one Series B Preferred share
purchase right (a "Series B Right") for each share of Class B Common (the
Series A Rights and the Series B Rights are hereinafter collectively
referred to as the "Rights"), (ii) execution of the Rights Agreement by
the Company and the Rights Agent in order to set forth certain terms and
conditions with respect to the Rights, and (iii) the appointment of the
Rights Agent under the Rights Agreement.

     B.     The Rights Agent and the Company then entered into the Rights
Agreement.

     C.     Section 27 of the Rights Agreement permits amendment thereof
upon execution by the Company and the Rights Agent of a written agreement
setting forth such amendment.

     D.     The Company and the Rights Agent desire to amend the Rights
Agreement to change the definition of "Final Expiration Date" in Section
7(a).

     NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the Company and the Rights Agent hereby agree that
the Rights Agreement is amended as follows:

     1.     Section 7(a) of the Rights Agreement is hereby deleted and the
following new Section 7(a) inserted in lieu thereof:

          The registered holder of any Right Certificate may
          exercise the Rights evidenced thereby (except as
          otherwise provided herein), in whole or in part, at
          any time after the Distribution Date, upon surrender
          of the Right Certificate, with the form of election to
          purchase on the reverse side thereof duly executed, to
          the Rights Agent at the principal office of the Rights
          Agent, together with payment of the Purchase Price for
          each one one-thousandth of a share of Series A
          Preferred or Series B Preferred as to which the Rights
          are exercised, at or prior to the first to occur of
          the following (i) the earlier of the Close of Business
          on February 14, 2001 or that time which is immediately
          prior to acceptance by the State Department of
          Assessments and Taxation of Maryland of articles of
          merger consummating the merger transaction by and
          between the Company and Rosemore Acquisition
          Corporation, a Maryland corporation ("RAC"), pursuant
          to the terms and conditions set forth in that certain
          Agreement and Plan of Merger dated April 7, 2000 by
          and among the Company, RAC and Rosemore, Inc., a
          Maryland corporation

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          (the "Final Expiration Date"), (ii) the
          time at which the Rights are redeemed as provided in
          Section 23 hereof (the "Redemption Date"), or (iii)
          the time at which such Rights are exchanged as
          provided in Section 24 hereof.

     2.   The Recitals set forth at the beginning of this
          First Amendment are incorporated herein.

     3.   Except as amended by this First Amendment, the Rights
          Plan shall remain in full force and effect.

     IN WITNESS WHEREOF, the parties hereto have caused this First
Amendment to be duly executed and attested, all as of the day and year
first above written.

ATTEST:                             FIRST UNION NATIONAL BANK,
                                    as Rights Agent


/s/ Kenneth E. Staab                By: /s/ James M. Clark
--------------------                -----------------------
                                    Name:     James M. Clark
                                    Title: Vice President


ATTEST:                             CROWN CENTRAL PETROLEUM
                                    CORPORATION


/s/ Dolores Rawlings                By: /s/ John E. Wheeler, Jr.
--------------------                -----------------------------
                                    Name:   John E. Wheeler, Jr.
                                    Title:  Executive Vice President -
                                            Chief Financial Officer