UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                  SCHEDULE 13G


                    Under the Securities Exchange Act of 1934
                                (Amendment No. 4)


                               MARKEL CORPORATION
                 ----------------------------------------------
                                (Name of Issuer)


                                  Common Stock
                 ----------------------------------------------
                         (Title of Class of Securities)


                                    570535104
                 ----------------------------------------------
                                 (CUSIP Number)


                                December 31, 2002
                 ----------------------------------------------
             (Date of Event which Requires Filing of this Statement)

Check the  appropriate box to designate the rule pursuant to which this Schedule
is filed:

|X|      Rule 13d-1(b)
|_|      Rule 13d-1(c)
|_|      Rule 13d-1(d)

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).







                                  SCHEDULE 13G



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

   1      NAME OF REPORTING PERSON
          SS. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

          Robert E. Torray & Co., Inc.
          N/A

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

   2      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP     (a) |_|
                                                               (b) |X|

--------- ----------------------------------------------------------------------
          SEC USE ONLY
   3


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

   4      CITIZENSHIP OR PLACE OF ORGANIZATION
          Maryland

----------------------- --------- ----------------------------------------------
                           5
                                  SOLE VOTING POWER
                                  0
   NUMBER OF SHARES
BENEFICIALLY OWNED BY
EACH REPORTING PERSON
         WITH

                        --------- ----------------------------------------------
                           6
                                  SHARED VOTING POWER
                                     473,513

                        --------- ----------------------------------------------
                           7
                                  SOLE DISPOSITIVE POWER
                                  0

                        --------- ----------------------------------------------
                           8
                                  SHARED DISPOSITIVE POWER
                                     473,513

----------- --------------------------------------------------------------------
    9
            AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
            703,618

------------ -------------------------------------------------------------------
    10
             CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
             CERTAIN SHARES                                                 |_|

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

    11
             PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
             7.15%

------------ -------------------------------------------------------------------
    12
             TYPE OF REPORTING PERSON
             IA
------------ -------------------------------------------------------------------






--------- ----------------------------------------------------------------------
   1
          NAME OF REPORTING PERSON
          SS. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

          Torray Corp.
          N/A
--------- ----------------------------------------------------------------------
   2
          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP     (a)  |_|
                                                               (b)  |X|
--------- ----------------------------------------------------------------------
   3
          SEC USE ONLY

--------- ----------------------------------------------------------------------
   4
          CITIZENSHIP OR PLACE OF ORGANIZATION
          Maryland

----------------------- --------- ----------------------------------------------
      NUMBER OF            5
        SHARES                    SOLE VOTING POWER
     BENEFICIALLY                 0
       OWNED BY
         EACH
      REPORTING
        PERSON
         WITH
                        --------- ----------------------------------------------
                           6
                                  SHARED VOTING POWER
                                     230,105
                        --------- ----------------------------------------------
                           7
                                  SOLE DISPOSITIVE POWER
                                  0
                        --------- ----------------------------------------------
                           8
                                  SHARED DISPOSITIVE POWER
                                     230,105
------------ -------------------------------------------------------------------
     9
             AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
             703,618
------------ -------------------------------------------------------------------
    10
             CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
             CERTAIN SHARES                                                 |_|

------------ -------------------------------------------------------------------
    11
             PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
             7.15%
------------ -------------------------------------------------------------------
    12
             TYPE OF REPORTING PERSON
             IA
------------ -------------------------------------------------------------------













--------- ----------------------------------------------------------------------
   1
          NAME OF REPORTING PERSON
          SS. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON

          Robert E. Torray
          N/A
--------- ----------------------------------------------------------------------
   2
          CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP     (a)  |_|
                                                               (b)  |X|

--------- ----------------------------------------------------------------------
   3
          SEC USE ONLY


--------- ----------------------------------------------------------------------
   4
          CITIZENSHIP OR PLACE OF ORGANIZATION
          United States

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

      NUMBER OF            5      SOLE VOTING POWER
        SHARES                    0
     BENEFICIALLY
       OWNED BY
         EACH
      REPORTING
        PERSON
         WITH
                        --------- ----------------------------------------------

                           6      SHARED VOTING POWER
                                     703,618

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

                           7      SOLE DISPOSITIVE POWER
                                  0
                        --------- ----------------------------------------------

                           8      SHARED DISPOSITIVE POWER
                                     703,618


------------ -------------------------------------------------------------------
     9
             AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
             703,618
------------ -------------------------------------------------------------------
    10
             CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
             CERTAIN SHARES                                                 |_|

------------ -------------------------------------------------------------------
    11
             PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
             7.15%
------------ -------------------------------------------------------------------
    12
             TYPE OF REPORTING PERSON
             IN, HC
------------ -------------------------------------------------------------------









Item 1.    (a).    Name of Issuer:  Markel Corporation

           (b).    Address of Issuer's Principal Executive Offices:

                   4251 Highwoods Parkway
                   Glen Allen, VA  23060


Item 2.    (a).    Name of Person Filing:

                  (i) Robert E. Torray & Co., Inc. ("Torray & Co.")
                  (ii) Torray Corp. ("Torray Corp.")
                  (iii) Robert E. Torray ("Torray")

           (b).   Address of Principal Business Office or, if none, Residence:

                  7501 Wisconsin Avenue
                  Suite 1100
                  Bethesda, MD  20814

           (c).   Citizenship or Place of Organization:

                  Torray & Co. and Torray Corp.:  Maryland
                  Torray:  United States

           (d).   Title of Class of Securities:  Common Stock

           (e).   CUSIP Number:  570535104


Item 3.    If this  statement is filed  pursuant  to  sections  240.13d-1(b)  or
           240.13d-2(b) or (c), check whether the person filing is a:

           (a)   [ ] Broker or dealer registered under section 15 of
                     the Act (15 U.S.C. 78o);
           (b)   [ ] Bank as defined in section 3(a)(6) of the
                     Act (15 U.S.C. 78c);
           (c)   [ ] Insurance company as defined in section 3(a)(19)
                     of the Act (15 U.S.C. 78c.);
           (d)   [ ] Investment company registered under section 8 of
                     the Investment Company Act of 1940 (15 U.S.C. 80a-8);
           (e)   [x] An investment adviser in accordance with
                     section 240.13d-1(b)(1)(ii)(E);
           (f)   [ ] An employee benefit plan or endowment fund in
                     accordance with section 240.13d-1(b)(1)(ii)(F);
           (g)   [x] A parent holding company or control person in
                     accordance with section 240.13d-1(b)(1)(ii)(G);
           (h)   [ ] A savings associations as defined in
                     section 3(b) of the Federal Deposit Insurance
                     Act (12 U.S.C. 1813);
           (i)   [ ] A church plan that is excluded from the
                     definition of an investment company under section
                     3(c)(14) of the Investment Company Act of 1940
                     (15 U.S.C. 80a-3);
           (j)   [ ] Group, in accordance with section 240.13d-1(b)(1)(ii)(J).


Item 4.   Ownership:

          Provide the following  information  regarding the aggregate number and
          percentage of the class of securities of the issuer identified in Item
          1.

          (a).    Amount beneficially owned:
                  (i)  Torray & Co.:     473,513
                 (ii)  Torray Corp.:     230,105
                (iii)  Torray:           703,618

          (b).    Percent of class:
                  (i)  Torray & Co.:     4.81%
                 (ii)  Torray Corp.:     2.34%
                (iii)  Torray:           7.15%

          (c).    Number of shares as to which the person has:

                  (1)  Sole power to vote or to direct the vote:

                  (i)   Torray & Co.:     0
                 (ii)   Torray Corp.:     0
                (iii)   Torray:           0







                  (2)   Shared power to vote or to direct the vote:

                  (i)   Torray & Co.:     473,513
                 (ii)   Torray Corp.:     230,105
                (iii)   Torray:           703,618

                  (3)   Sole power to dispose or to direct the disposition of:

                  (i)   Torray & Co.:     0
                 (ii)   Torray Corp.:     0
                (iii)   Torray:           0

                  (4)   Shared power to dispose or to direct the disposition of:

                  (i)   Torray & Co.:     473,513
                 (ii)   Torray Corp.:     230,105
                (iii)   Torray:           703,618

Item 5.   Ownership of Five Percent or Less of a Class:

          Not Applicable

Item 6.   Ownership of More Than Five Percent on Behalf of Another Person:

          Not Applicable

Item 7.   Identification and  Classification of Subsidiaries  which Acquired the
          Security Being Reported on by the Parent Holding Company:

          Not Applicable

Item 8.   Identification and Classification of Members of the Group:

          Not Applicable

Item 9.   Notice of Dissolution of Group:

          Not Applicable







Item 10.  Certification:

          By  signing  below I certify  that,  to the best of my  knowledge  and
          belief, the securities referred to above were acquired and are held in
          the ordinary course of business and were not acquired and are not held
          for the purpose of or with the effect of changing or  influencing  the
          control of the issuer of the  securities and were not acquired and are
          not held in  connection  with or as a participant  in any  transaction
          having that purpose or effect.

          In accordance with Rule 13d-4 of the Securities  Exchange Act of 1934,
          each of the  persons  filing this  statement  expressly  disclaim  the
          beneficial  ownership of the securities  covered by this statement and
          the filing of this report  shall not be  construed  as an admission by
          such persons that they are the beneficial owners of such securities.







                                   SIGNATURES

     After  reasonable  inquiry and to the best of my  knowledge  and belief,  I
certify that the information  set forth in this statement is true,  complete and
correct.

                                           ROBERT E. TORRAY & CO., INC.

Date:  March 21, 2003                      By: /s/William Lane
                                               -----------------------------
                                               William Lane
                                               Executive Vice President


                                           TORRAY CORP.

Date:  March 21, 2003                      By: /s/William Lane
                                               ----------------------------
                                               William Lane
                                               Vice President


                                           ROBERT E. TORRAY

Date:  March 21, 2003                      By: /s/Robert E. Torray
                                               ----------------------------
                                               Robert E. Torray










                                    EXHIBIT 1

JOINT FILING  AGREEMENT  AMONG ROBERT E. TORRAY & CO.,  INC.,  TORRAY CORP.  AND
ROBERT E. TORRAY

WHEREAS,  in accordance with Rule 13d-1(k) under the Securities and Exchange Act
of 1934 (the "Act"), only one joint statement and any amendments thereto need to
be filed  whenever  one or more persons are required to file such a statement or
any amendments  thereto pursuant to Section 13(d) of the Act with respect to the
same securities, provided that said persons agree in writing that such statement
or amendments thereto is filed on behalf of each of them;

     NOW, THEREFORE, the parties hereto agree as follows:

ROBERT E. TORRAY & CO., INC., TORRAY CORP. AND ROBERT E. TORRAY hereby agree, in
accordance with Rule 13d-1(k) under the Act, to file a statement on Schedule 13G
relating to their  ownership of Common Stock of the Issuer and do hereby further
agree that said statement shall be filed on behalf of each of them.

                                           ROBERT E. TORRAY & CO., INC.

Date:  March 21, 2003                      By: /s/William Lane
                                               -----------------------------
                                               William Lane
                                               Executive Vice President


                                           TORRAY CORP.

Date:  March 21, 2003                      By: /s/William Lane
                                               ----------------------------
                                               William Lane
                                               Vice President


                                           ROBERT E. TORRAY

Date:  March 21, 2003                      By: /s/Robert E. Torray
                                               ----------------------------
                                               Robert E. Torray