EXHIBIT 5.1

                      [ANDREWS & KURTH L.L.P. LETTERHEAD]


                                December 10, 2002



Transcontinental Gas Pipe Line Corporation
2800 Post Oak Boulevard
Houston, Texas  77251

Gentlemen:

                  We have acted as special counsel to Transcontinental Gas Pipe
Line Corporation, a Delaware corporation (the "Company"), in connection with the
preparation and filing of the Registration Statement on Form S-4 by the Company
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Act"), on December 10, 2002 (the
"Registration Statement"), with respect to the issuance by the Company of up to
$325,000,000 aggregate principal amount of its 8?% Series B Senior Notes due
2012 (the "New Notes") in exchange for up to $325,000,000 aggregate principal
amount of its outstanding 8?% Series A Senior Notes due 2012 (the "Old Notes").
The New Notes are to be issued in accordance with the provisions of the
Indenture, dated as of July 3, 2002 (the "Indenture"), by and between the
Company and Citibank N.A., as trustee. Citibank N.A. has been succeeded as
trustee under the Indenture by Wells Fargo Bank, N.A. The New Notes are to be
issued pursuant to an exchange offer (the "Exchange Offer") by the Company to
holders of the issued and outstanding Old Notes, as contemplated by the
Registration Rights Agreement, dated as of July 3, 2002 (the "Registration
Rights Agreement"), by and between the Company and Salomon Smith Barney Inc.
("Salomon").

                  This opinion is being furnished in accordance with the
requirements of Item 601(b)(5) of Regulation S-K under the Act.

                  In connection with this opinion, we have examined originals or
copies, certified or otherwise identified to our satisfaction, of:

                  (i) the Registration Statement, including the form of
         prospectus included therein and the documents incorporated by reference
         therein;

                  (ii) the Company's Certificate of Incorporation and By-laws,
         each as amended to date;


Transcontinental Gas Pipe Line Corporation
December 10, 2002
Page 2

                  (iii) an executed copy of the Indenture;

                  (iv) an executed copy of the Registration Rights Agreement;

                  (v) the Form T-1 of Wells Fargo Bank, N.A. (the "Trustee"), as
         successor trustee to Citibank N.A. under the Indenture , filed as an
         exhibit to the Registration Statement; and

                  (vi) the form of the New Notes.

                  We have also examined originals or copies certified or
otherwise identified to our satisfaction of such other certificates of public
officials, officers and representatives of the Company and such other persons,
and we have made such investigations of law, as we have deemed appropriate as a
basis for the opinions expressed below.

                  In rendering the opinion set forth below, we have assumed and
have not verified (i) the genuineness of the signatures on all documents that we
have examined, (ii) the legal capacity of all natural persons, (iii) the
authenticity of all the documents supplied to us as originals, and (iv) the
conformity to the authentic originals of all documents supplied to us as
certified or photostatic or faxed copies. In conducting our examination of such
documents, we have assumed that the parties to such documents had the power,
corporate or other, to enter into and perform all obligations thereunder and
have also assumed the due authorization by all requisite action, corporate or
other, and the due execution and delivery by such parties of such documents and
that, except as set forth below with respect to the Company, to the extent such
documents purport to constitute agreements, such documents constitute valid and
binding obligations of such parties. As to any facts material to the opinion
expressed herein which we have not independently established or verified, we
have relied upon oral or written statements and representations of officers and
other representatives of the Company and others.

                  Our opinion set forth herein is limited to the laws of the
State of New York that are normally applicable to transactions of the type
contemplated by the Exchange Offer and, to the extent that judicial or
regulatory orders or decrees or consents, approvals, licenses, authorizations,
validations, filings, recordings or registrations with governmental authorities
are relevant, to those required under such laws (all of the foregoing being
referred to as "Opined-on-Law"). We do not express any opinion with respect to
the law of any jurisdiction other than Opined-on-Law or as to the effect of any
such other law on the opinion stated herein.

                  Based upon and subject to the foregoing, having due regard for
such legal considerations as we deem relevant, and subject to the limitations,
qualifications, exceptions and assumptions set forth herein, we are of the
opinion that when the New Notes (in the form examined by us) have been duly
executed by the Company, authenticated by the Trustee in accordance with the
terms of the Indenture and delivered upon consummation of the Exchange Offer
against receipt of Old Notes surrendered in exchange therefor in accordance with
the terms of the Exchange Offer, the Registration Rights Agreement and the
Indenture, the New Notes will



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December 10, 2002
Page 3

constitute valid and binding obligations of the Company, enforceable against the
Company in accordance with their terms under the laws of the State of New York,
except, to the extent that enforcement thereof may be limited by (i) bankruptcy,
insolvency (including, without limitation, all laws relating to fraudulent
transfer or conveyance), reorganization, moratorium, or other similar laws
affecting creditors' rights generally and (ii) general principles of equity
(regardless of whether enforcement is sought in a proceeding at law or in
equity).

                  In rendering the opinion set forth above, we have assumed that
the execution and delivery by the Company of the Indenture and the New Notes,
and the performance by the Company of its obligations under the Indenture and
the New Notes, do not and will not violate, conflict with or constitute a
default under any agreement or instrument to which either the Company or its
properties are subject. In addition, we have assumed that the Company is validly
existing and in good standing under the laws of its jurisdiction of organization
and has complied with all aspects of such laws in connection with the issuance
of the New Notes and the related transactions.

                  We hereby consent to the filing of this opinion with the
Commission as an exhibit to the Registration Statement. We also consent to the
reference to our firm under the caption "Legal Matters" in the Registration
Statement. In giving this consent, we do not thereby admit that we are included
in the category of persons whose consent is required under Section 7 of the Act
or the rules and regulations of the Commission. This opinion is expressed as of
the date hereof, and we disclaim any undertaking to advise you of any subsequent
changes in the facts stated or assumed herein or of any subsequent changes in
applicable law.



                                                     Very truly yours,

                                                     /s/ Andrews & Kurth L.L.P.