MARCUS C. BENNETT
LIMITED POWER OF ATTORNEY FOR
SECTION 16 REPORTING OBLIGATIONS

    Know all by these presents, that the undersigned hereby makes, constitutes
and appoints each of Roselyn R. Bar and M. Guy Brooks, III, each acting individ-
ually, as the undersigned's true and lawful attorney-in-fact, with full power
and authority as hereinafter described on behalf of and in the name, place and
stead of the undersigned to:

    (1) prepare, execute, acknowledge, deliver and file Forms 3, 4, and 5 (inc-
luding any amendments thereto) with respect to the securities of Martin Marietta
Materials, Inc. a North Carolina corporation (the "Company"), with the United
States Securities and Exchange Commission, any national securities exchanges and
the Company, as considered necessary or advisable under Section 16(a) of the
Securities Exchange Act of 1934 and the rules and regulations promulgated there-
under, as amended from time to time (the "Exchange Act");

    (2) seek or obtain, as the undersigned's representative and on the under-
signed's behalf, information on transactions in the Company's securities from
any third party, including brokers, employee benefit plan administrators and
trustees, and the undersigned hereby authorizes any such person to release any
such information to the undersigned and approves and ratifies any such release
of information; and

    (3) perform any and all other acts which in the discretion of such attorney-
in-fact are necessary or desirable for and on behalf of the undersigned in con-
nection with the foregoing.

    The undersigned acknowledges that:

    (1) This Power of Attorney authorizes, but does not require, each such
attorney-in-fact to act in their discretion on information provided to such
attorney-in-fact without independent verification of such information;

    (2) any documents prepared and/or executed by either such attorney-in-fact
on behalf of the undersigned pursuant to this Power of Attorney will be in such
form and will contain such information and disclosure as such attorney-in-fact,
in his or her discretion, deems necessary or desirable;

    (3) neither the Company nor either of such attorneys-in-fact assumes (i) any
liability for the undersigned's responsibility to comply with the requirement of
the Exchange Act, (ii) any liability of the undersigned for any failure to
comply with such requirements, or (iii) any obligation or liability of the
undersigned for profit disgorgement under Section 16(b) of the Exchange Act; and

    (5) this Power of Attorney does not relieve the undersigned from responsi-
bility for compliance with the undersigned's obligations under the Exchange Act,
including without limitation the reporting requirements under Section 16 of the
Exchange Act.

    The undersigned hereby gives and grants each of the foregoing attorneys-in-
fact full power and authority to do and perform all and every act and thing
whatsoever requisite, necessary or appropriate to be done in and about the fore-
going matters as fully to all intents and purposes as the undersigned might or
could do if present, hereby ratifying all that each such attorney-in-fact of,
for and on behalf of the undersigned, shall lawfully do or cause to be done by
virtue of this Limited Power of Attorney.

    This Power of Attorney shall remain in full force and effect until revoked
by the undersigned in a signed writing delivered to each such attorney-in-fact.

    IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 24th day of June, 2004.



/s/Marcus C. Bennett





STATE OF MARYLAND

COUNTY OF MONTGOMERY

    On this 24th day of June, 2004, Marcus C. Bennett personally
appeared before me, and acknowledged that he executed the foregoing instrument
for the purposes therein contained.

    IN WITNESS WHEREOF, I have hereunto set my hand and official seal.



/s/ Mary A. Simonsen
Notary Public

My Commission Expires:  January 1, 2008