Exhibit 5.1
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               [McGuire, Woods, Battle & Boothe LLP Letterhead]


                               October 28, 1998



CSX Corporation
One James Center
901 East Cary Street
Richmond, VA 23219

Ladies and Gentlemen:

     We have advised CSX Corporation, a Virginia corporation (the "Company"), in
connection with (i) the Registration Statement on Form S-3 (File No. 333-53191)
(the "Registration Statement") filed by the Company with the Securities and
Exchange Commission for the purpose of registering under the Securities Act of
1933, as amended, the Company's Debt Securities, Debt Warrants, Preferred Stock,
Preferred Stock Warrants and Depositary Shares, from the sale of which the
Company may receive proceeds of up to $750,000,000, to be offered from time to
time by the Company on terms to be determined at the time of the offering and
(ii) the issuance by the Company of up to $400,000,000 aggregate principal
amount of the Company's 6.25% Notes due 2008 (the "Notes") as described in the
Company's Prospectus, dated August 11, 1998, which is a part of the Registration
Statement, and Prospectus Supplement, dated October 23, 1998 (the "Prospectus
Supplement"), and pursuant to an indenture dated as of August 1, 1990 between
the Company and The Chase Manhattan Bank, as trustee (the "Trustee"), as
supplemented by a First Supplemental Indenture dated as of June 15, 1991, a
Second Supplemental Indenture dated as of May 6, 1997 and a Third Supplemental
Indenture dated as of April 22, 1998 (the indenture, as so supplemented, is
herein called the "Indenture") and the Action of Authorized Pricing Officers
adopted as of October 23, 1998 (the "Action of Authorized Pricing Officers"),
and the public offering of the Notes pursuant to an Underwriting Agreement,
dated October 23, 1998 (the "Underwriting Agreement"), among the Company and the
Underwriters named on Schedule I thereto. Capitalized terms used and not defined
herein shall have the meanings assigned to them in the Registration Statement.

     We have examined such corporate records, certificates and other documents,
and reviewed such questions of law, as we have considered necessary or
appropriate for the purpose of this opinion.

     On the basis of such examination and review, we advise you that, in our
opinion, when the Notes have been duly issued and sold in the manner
contemplated by the Registration Statement and the Prospectus Supplement, and
assuming due authentication thereof by the Trustee or the Authenticating Agent
in accordance with the provisions of the Indenture, as amended and supplemented,
the Notes will constitute valid and legally binding obligations of the Company,
enforceable against the


 
Company in accordance with their terms, subject to bankruptcy, insolvency,
fraudulent transfer, reorganization, moratorium and similar laws of general
applicability relating to or affecting creditors' rights and to general equity
principles.

     We hereby consent to the filing of this opinion as an exhibit to the
Company's Current Report on Form 8-K and the incorporation of this opinion by
reference in the Registration Statement and to references to us under the
heading "Validity of Securities" in the Registration Statement and the heading
"Legal Matters" in the Prospectus Supplement relating to the Notes. We do not
admit by giving this consent that we are in the category of persons whose
consent is required under Section 7 of the Act.

                                   Very truly yours,

                                   /s/ McGuire, Woods, Battle & Boothe LLP