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                                                                    EXHIBIT 3.21


                                STATE OF DELAWARE

                        OFFICE OF THE SECRETARY OF STATE

                        --------------------------------



     I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF MERGER,
WHICH MERGES:

     "CHANCELLOR MEDIA CORPORATION OF BOSTON", A DELAWARE CORPORATION, 

     WITH AND INTO "CHANCELLOR MEDIA CORPORATION OF MASSACHUSETTS" UNDER THE
NAME OF "CHANCELLOR MEDIA CORPORATION OF MASSACHUSETTS", A CORPORATION ORGANIZED
AND EXISTING UNDER THE LAWS OF THE STATE OF DELAWARE, AS RECEIVED AND FILED IN
THIS OFFICE THE THIRTY-FIRST DAY OF JULY, A.D. 1998, AT 11 O'CLOCK A.M.

     A FILED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO THE NEW CASTLE
COUNTY RECORDER OF DEEDS.




                                      /s/ EDWARD J. FREEL
                                      -----------------------------------
                                      Edward J. Freel, Secretary of State

                                      AUTHENTICATION:    9229078

                    [SEAL]                      DATE: 07-31-98
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                              CERTIFICATE OF MERGER
                                       OF
                     CHANCELLOR MEDIA CORPORATION OF BOSTON
                                      INTO
                  CHANCELLOR MEDIA CORPORATION OF MASSACHUSETTS

     The undersigned corporation, organized and existing under and by virtue of
the General Corporation Law of the State of Delaware,

     DOES HEREBY CERTIFY:

     FIRST: That the name and state of incorporation of each of the constituent
corporations of the merger is as follows:



    NAME                                                STATE OF INCORPORATION
    ----                                                ----------------------
                                                      
    Chancellor Media Corporation of Boston                     Delaware
    Chancellor Media Corporation of Massachusetts              Delaware


     SECOND: That a Plan and Agreement of Merger between the parties to the
merger has been approved, adopted, certified, executed and acknowledged by each
of the constituent corporations in accordance with the requirements of Section
251 of the General Corporation Law of the State of Delaware.

     THIRD: That the name of the surviving corporation is Chancellor Media
Corporation of Massachusetts.

     FOURTH: The Certificate of Incorporation of Chancellor Media Corporation of
Massachusetts shall be the Certificate of Incorporation of the surviving
corporation, to remain unchanged until amended in accordance with the provisions
thereof and of applicable law.

     FIFTH: That the executed Plan and Agreement of Merger is on file at the
principal place of business of the surviving corporation. The address of the
principal place of business of the surviving corporation is 433 E. Las Colinas
Blvd., Suite 1130, Irving, Texas 75039.



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     SIXTH: That a copy of the Plan and Agreement of Merger will be furnished by
the surviving corporation on request and without cost to any stockholder of any
constituent corporation.




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Dated:      July 31         ,1998
      ----------------------

                                    CHANCELLOR MEDIA CORPORATION OF 
                                    MASSACHUSETTS


                                    By: /s/ ANDREA HULCY
                                       -----------------------------------------
                                       Andrea Hulcy
                                       Vice President and Assistant Secretary




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                                STATE OF DELAWARE

                        OFFICE OF THE SECRETARY OF STATE

                        --------------------------------

     I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF AMENDMENT
OF "EVERGREEN MEDIA CORPORATION OF MASSACHUSETTS", CHANGING ITS NAME FROM
"EVERGREEN MEDIA CORPORATION OF MASSACHUSETTS" TO "CHANCELLOR MEDIA CORPORATION
OF MASSACHUSETTS", FILED IN THIS OFFICE ON THE SEVENTEENTH DAY OF OCTOBER,
A.D. 1997, AT 4:30 O'CLOCK P.M.

     A CERTIFIED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO THE NEW CASTLE
COUNTY RECORDER OF DEEDS FOR RECORDING.



                                      /s/ EDWARD J. FREEL
                                      -----------------------------------
                                      Edward J. Freel, Secretary of State

                                      AUTHENTICATION:    8709859

                  [SEAL]                        DATE: 10-20-97

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                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                  EVERGREEN MEDIA CORPORATION OF MASSACHUSETTS

     Pursuant to Section 242 of the General Incorporation Law of the State of
Delaware, Evergreen Media Corporation of Massachusetts (the "Corporation"), a
Delaware corporation, hereby certifies that:

     1.   The Certificate of Incorporation of the Corporation is hereby amended
          by deleting the present Article FIRST and inserting in lieu thereof a
          new Article FIRST, as follows:

          FIRST: The name of the Corporation (hereinafter sometimes referred to
          as the "Corporation" is:

          "CHANCELLOR MEDIA CORPORATION OF MASSACHUSETTS"

     2.   The Sole Director and Sole Shareholder of the Corporation, by written
          consent, adopted, approved and ratified the foregoing Amendment.

     IN WITNESS WHEREOF, the Corporation has caused the Certificate of Amendment
to be signed and executed in its corporate name by Omar Choucair, its Vice
President, on this 17 day of October, 1997.

                                               EVERGREEN MEDIA CORPORATION    
                                               OF MASSACHUSETTS,              
                                               a Delaware Corporation         
                                                                              
                                               By: /s/ OMAR CHOUCAIR          
                                                  -----------------------------
                                               Name: Omar Choucair            
                                               Title: Vice President          



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                                STATE OF DELAWARE

                        OFFICE OF THE SECRETARY OF STATE

                        --------------------------------

     I, EDWARD J. FREEL, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO HEREBY
CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF AMENDMENT
OF "PYRAMID COMMUNICATIONS OF MASSACHUSETTS, INC.", CHANGING ITS NAME FROM
"PYRAMID COMMUNICATIONS OF MASSACHUSETTS, INC." TO "EVERGREEN MEDIA CORPORATION
OF MASSACHUSETTS", FILED IN THIS OFFICE ON THE SEVENTEENTH DAY OF JANUARY,
A.D. 1996, AT 4 O'CLOCK P.M.



                                      /s/ EDWARD J. FREEL
                                      -----------------------------------
                                      Edward J. Freel, Secretary of State

                                      AUTHENTICATION:    7793865

                    [SEAL]                      DATE: 01-18-96


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                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                  PYRAMID COMMUNICATIONS OF MASSACHUSETTS, INC.

     Pursuant to Section 242 of the General Corporation Law of the State of
Delaware, Pyramid Communications of Massachusetts, Inc. (the "Corporation"), a
Delaware corporation, hereby certifies that:

     1.   The Certificate of Incorporation of the Corporation is hereby amended
          by deleting the present Article FIRST and inserting in lieu thereof a
          new Article FIRST, as follows:

          FIRST: The name of the Corporation (hereinafter sometimes referred to
          as the "Corporation") is:

                    "EVERGREEN MEDIA CORPORATION OF MASSACHUSETTS"

     2.   The Board of Directors and Stockholders of the Corporation, by written
          consent, adopted, approved and ratified the foregoing Amendment.

     IN WITNESS WHEREOF, the Corporation has caused this Certificate of
Amendment to be signed and executed in its corporate name by Matthew E. Devine,
its assistant secretary, on this 17th day of January, 1996.



                                             PYRAMM COMMUNICATIONS OF         
                                             MASSACHUSETTS, INC.,             
                                             a Delaware corporation           
                                                                         
                                             By: /s/ Matthew E. Devine        
                                                -------------------------------
                                                   Matthew E. Devine          
                                                   Assistant Secretary        

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                                STATE OF DELAWARE

                        OFFICE OF THE SECRETARY OF STATE

                        --------------------------------

     I, WILLIAM T. QUILLEN, SECRETARY OF STATE OF THE STATE OF DELAWARE, DO
HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF
INCORPORATION OF "PYRAMID COMMUNICATIONS OF MASSACHUSETTS, INC." FILED IN THIS
OFFICE ON THE SEVENTEENTH DAY OF DECEMBER, A.D. 1993, AT 12:15 O'CLOCK P.M.

     A CERTIFIED COPY OF THIS CERTIFICATE HAS BEEN FORWARDED TO KENT COUNTY
RECORDER OF DEEDS FOR RECORDING.


                             * * * * * * * * * * * *





                                      /s/ WILLIAM T. QUILLEN
                                      ---------------------------------------
                                      William T. Quillen, Secretary of State

                                      AUTHENTICATION:    4202772

                     [SEAL]                     DATE: 121-20-93
         
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                          CERTIFICATE OF INCORPORATION

                                       OF

                 PYRAMID COMMUNICATIONS Of MASSACHUSETTS, INC.

     FIRST: The name of the corporation (hereinafter sometimes referred to as
the "Corporation") is: 

                 Pyramid Communications of Massachusetts, Inc.

     SECOND: The address of the registered office of the Corporation in the
State of Delaware is 32 Loockerman Square, Suite L-100, Kent County, Dover,
Delaware 19901. The name of its registered agent at such address is The
Prentice-Hall Corporation System, Inc.

     THIRD: The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of the State of Delaware.

     FOURTH: The aggregate number of all classes of shares which the Corporation
shall have authority to issue is one thousand (1,000) shares of common stock
with a par value of $.01 per share.

     No holder of shares of the Corporation of any class, now or hereafter
authorized, shall have any preferential or preemptive right to subscribe for,
purchase or receive any share of the Corporation of any class, now or hereafter
authorized, or any options of warrants for such shares, or any rights to 
subscribe to or purchase such shares, or any securities convertible into or
exchangeable for such shares, which may at any time or from time to time be
issued, sold or offered for sale by the Corporation; provided, however, that in
connection with the issuance or sale of any such shares or securities, the Board
of Directors of the Corporation may, in its sole discretion, offer such shares
or securities, or any part thereof, for purchase or subscription by the




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holders of shares of the Corporation, except as may otherwise be provided by
this Certificate of Incorporation as from time to time amended.

     At all times, each holder of common stock of the Corporation shall be
entitled to one vote for each share of common stock held by such stockholder
standing in the name of such stockholder on the books of the Corporation.

     FIFTH: The name and address of the Incorporator is as follows:

                        Sylvia L. Adams
                        LATHAM & WATKINS
                        1001 Pennsylvania Avenue, Suite 1300
                        Washington, D.C. 20004

     SIXTH: In furtherance and not in limitation of the power conferred by
statute, the Board of Directors is expressly authorized to make, alter or repeal
the Bylaws of the Corporation.

     SEVENTH: No director of the Corporation shall be liable to the Corporation
or its stockholders for monetary damages for the breach of fiduciary duty as a
director, except for liability (i) for any breach of the director's duty of
loyalty to the Corporation or its stockholders, (ii) for acts or omissions not 
in good faith or which involved intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv) 
for any transaction from which the director derived an improper personal 
benefit.

     EIGHTH: Election of directors need not be by written ballot unless the
Bylaws of the Corporation shall so provide.

     NINTH: The Corporation reserves the right to amend, alter, change or repeal
any provisions contained in this Certificate of Incorporation, in the manner now
or hereafter prescribed by the law of the State of Delaware. All rights
conferred upon stockholders herein are granted subject to this reservation.






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     I, THE UNDERSIGNED, being the sole incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the General Corporation Law of the
State of Delaware, do make this certificate, herein declaring and certifying
that this is my act and deed and the facts herein stated are true, and
accordingly have hereunto set my hand this 16th day of December, 1993.



                                             /s/ SYLVIA L. ADAMS
                                             ------------------------------
                                             Sylvia L. Adams
                                             Incorporator




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