NOTICE OF GUARANTEED DELIVERY
                                 FOR TENDER OF
                            ANY AND ALL OUTSTANDING
                       8.71% SERIES A CAPITAL SECURITIES
                (LIQUIDATION AMOUNT $1,000 PER CAPITAL SECURITY)
                                       OF
                             MARKEL CAPITAL TRUST I
                      FULLY AND UNCONDITIONALLY GUARANTEED
                             BY MARKEL CORPORATION

         This Notice of Guaranteed Delivery, or one substantially equivalent to
this form, must be used to accept the Exchange Offer (as defined below) if (i)
certificates for the Trust's (as defined below) 8.71% Series A Capital
Securities (the "Old Capital Securities") are not immediately available, (ii)
Old Capital Securities, the Letter of Transmittal and all other required
documents cannot be delivered to The Chase Manhattan Bank (the "Exchange Agent")
on or prior to 5:00 P.M. New York time, on the Expiration Date (as defined in
the Prospectus referred to below) or (iii) the procedures for delivery by
book-entry transfer cannot be completed on a timely basis. This Notice of
Guaranteed Delivery may be delivered by hand, overnight courier or mail, or
transmitted by facsimile transmission, to the Exchange Agent. See "The Exchange
Offer--Procedures for Tendering Old Capital Securities" in the Prospectus. In
addition, in order to utilize the guaranteed delivery procedure to tender Old
Capital Securities pursuant to the Exchange Offer, a completed, signed and dated
Letter of Transmittal relating to the Old Capital Securities (or facsimile
thereof) must also be received by the Exchange Agent prior to 5:00 P.M. New York
time on the Expiration Date. Capitalized terms not defined herein have the
meanings assigned to them in the Prospectus.

                 The Exchange Agent For The Exchange Offer Is:
                            The Chase Manhattan Bank


By Registered or Certified Mail       Facsimile Transmissions:      By Hand or Overnight Delivery
                                     (Eligible Institutions Only)

 
   The Chase Manhattan Bank                                            The Chase Manhattan Bank
    Global Trust Services                (212) 946-8154                  Global Trust Services
    450 West 33rd Street,                                                 450 West 33rd Street,
         15th Floor                  Confirm by Telephone:                     15th Floor
  New York, New York 10001               (212) 946-3049                 New York, New York 10001
   Attn: Phil Jones, Trust                                               Attn: Phil Jones, Trust
           Officer                                                                Officer



         Delivery of this Notice of Guaranteed Delivery to an address other than
as set forth above or transmission of this Notice of Guaranteed Delivery via
facsimile to a number other than as set forth above will not constitute a valid
delivery.






         THIS NOTICE OF GUARANTEED DELIVERY IS NOT TO BE USED TO GUARANTEE
SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE
GUARANTEED BY AN "ELIGIBLE INSTITUTION" UNDER THE INSTRUCTIONS THERETO, SUCH
SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE
SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.


Ladies and Gentlemen:

         The undersigned hereby tenders to Markel Corporation, a Virginia
corporation (the "Corporation") and to Markel Capital Trust I, a Delaware
business trust (the "Trust"), upon the terms and subject to the conditions set
forth in the Prospectus dated May __, 1997 (as the same may be amended or
supplemented from time to time, the "Prospectus"), and the related Letter of
Transmittal (which together constitute the "Exchange Offer"), receipt of which
is hereby acknowledged, the aggregate principal amount of Old Capital Securities
set forth below pursuant to the guaranteed delivery procedures set forth in the
Prospectus under the caption "The Exchange Offer--Procedures for Tendering Old
Capital Securities."

Aggregate Liquidation Amount                 Name(s) of Registered Holder(s):
Amount Tendered:

$-----------------------------               -----------------------------------

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

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

Certificate No(s).
if available: _____________________

Total Liquidation Amount Represented by
Old Capital Securities Certificate(s):

$------------------------------

If Old Capital Securities will be tendered by book-entry transfer, provide the
following information:

DTC Account Number: ____________________

Date: ___________________________________

         *Must be in denominations of a Liquidation Amount of $1,000 and any
integral multiple thereof, and not less than $100,000 aggregate Liquidation
Amount.






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

         All authority herein conferred or agreed to be conferred shall survive
the death or incapacity of the undersigned and every obligation of the
undersigned hereunder shall be binding upon the heirs, personal representatives,
successors and assigns of the undersigned.

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

                                PLEASE SIGN HERE

X _____________________________________         _______________________________

X _____________________________________         _______________________________
    Signature(s) of Owner(s) or Authorized        Date
    Signatory

Area Code and Telephone Number: _________________________

         Must be signed by the holder(s) of the Old Capital Securities as their
name(s) appear(s) on certificates for Old Capital Securities or on a security
position listing, or by person(s) authorized to become registered holder(s) by
endorsement and documents transmitted with this Notice of Guaranteed Delivery.
If signature is by a trustee, executor, administrator, guardian,
attorney-in-fact, officer or other person acting in a fiduciary or
representative capacity, such person must set forth his or her full title below.


                                    Please print name(s) and address(es)
Name(s):            _________________________________________________________

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

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

Capacity:           _________________________________________________________

Address(es):        _________________________________________________________

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

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






              THE GUARANTEE ON THE REVERSE SIDE MUST BE COMPLETED

                                   GUARANTEE
                    (NOT TO BE USED FOR SIGNATURE GUARANTEE)

         The undersigned, a firm or other entity identified in Rule 17Ad-15
under the Securities Exchange Act of 1934, as amended, as an "eligible guarantor
institution", including (as such terms are defined therein): (i) a bank; (ii) a
broker, dealer, municipal securities broker, municipal securities dealer,
government securities broker, government securities dealer; (iii) a credit
union; (iv) a national securities exchange, registered securities association or
clearing agency; or (v) a savings association that is a participant in a
Securities Transfer Association recognized program (each of the foregoing being
referred to as an "Eligible Institution"), hereby guarantees to deliver to the
Exchange Agent, at one of its addresses set forth above, either the Old Capital
Securities tendered hereby in proper form for transfer, or confirmation of the
book-entry transfer of such Old Capital Securities to the Exchange Agent's
account at the Depository Trust Company ("DTC"), pursuant to the procedures for
book-entry transfer set forth in the Prospectus, in either case together with
one or more properly completed and duly executed Letter(s) of Transmittal (or
facsimile thereof) and any other required documents within five business days
after the date of execution of this Notice of Guaranteed Delivery.

         The undersigned acknowledges that it must deliver the Letter(s) of
Transmittal and the Old Capital Securities tendered hereby to the Exchange Agent
within the time period set forth above and that failure to do so could result in
a financial loss to the undersigned.

- ------------------------------------     -----------------------------------
         Name of Firm                            Authorized Signature

- ------------------------------------     -----------------------------------
         Address                                       Title

- ------------------------------------     -----------------------------------
         Zip Code                                (Please Type or Print)

Area Code and Telephone No. ___________     Dated:______________________________

NOTE: DO NOT SEND CERTIFICATES FOR OLD CAPITAL SECURITIES WITH THIS FORM.
CERTIFICATES FOR OLD CAPITAL SECURITIES SHOULD ONLY BE SENT WITH YOUR LETTER OF
TRANSMITTAL.