AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON AUGUST 9, 2004

REGISTRATION NO. 333-114796
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1 TO

FORM S-4
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933
---------------------
CSX TRANSPORTATION, INC.
(Exact name of Registrant as specified in its charter)

<Table>

COMMONWEALTH OF VIRGINIA 4011 54-6000720
(State or other jurisdiction of (Primary Standard Industrial (I.R.S. Employer
incorporation or organization) Classification Code No.) Identification No.)
</Table>

NYC NEWCO, INC.
(Exact name of Registrant as specified in its charter)

<Table>

COMMONWEALTH OF VIRGINIA 4011 51-0500921
(State or other jurisdiction of (Primary Standard Industrial (I.R.S. Employer
incorporation or organization) Classification Code No.) Identification No.)
</Table>

500 WATER STREET, 15TH FLOOR
JACKSONVILLE, FLORIDA 32202
(904) 359-3100
(Address, including zip code, and telephone number, including area code, of
Registrant's principal executive offices)

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

ELLEN M. FITZSIMMONS, ESQ.
SENIOR VICE PRESIDENT -- LAW AND PUBLIC AFFAIRS
CSX TRANSPORTATION, INC.
500 WATER STREET, 15TH FLOOR
JACKSONVILLE, FLORIDA 32202
(904) 359-3100
(Name, address, including zip code, and telephone number, including area code,
of agent for service)

WITH COPIES OF ALL COMMUNICATIONS TO:

STEVEN A. COHEN, ESQ.
JAMES COLE, JR., ESQ.
WACHTELL, LIPTON, ROSEN & KATZ
51 WEST 52ND STREET
NEW YORK, NEW YORK 10019
(212) 403-1000

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

APPROXIMATE DATE OF COMMENCEMENT OF PROPOSED SALE TO PUBLIC: As soon as
practicable after the effective date of this registration statement and the date
upon which all other conditions to the exchange offer and consent solicitation
described in the enclosed prospectus and consent solicitation statement have
been satisfied or waived.
If the securities being registered on this Form are being offered in
connection with the formation of a holding company and there is compliance with
General Instruction G, check the following box. [ ]
If this Form is filed to register additional securities for an offering
pursuant to Rule 462(b) under the Securities Act, check the following box and
list the Securities Act registration statement number of the earlier effective
registration statement for the same offering. [ ]
If this Form is a post-effective amendment filed pursuant to Rule 462(d)
under the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering. [X]

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

CALCULATION OF REGISTRATION FEE

<Table>
<Caption>
- ---------------------------------------------------------------------------------------------------------------------------------
- ---------------------------------------------------------------------------------------------------------------------------------
TITLE OF EACH CLASS OF AMOUNT TO BE PROPOSED MAXIMUM AGGREGATE AMOUNT OF
SECURITIES TO BE REGISTERED REGISTERED(1) OFFERING PRICE(1), (2) REGISTRATION FEE
- ---------------------------------------------------------------------------------------------------------------------------------

9 3/4% Notes Due June 15, 2020............ $231,000,000 $310,233,000 $39,307(1)(3)
- ---------------------------------------------------------------------------------------------------------------------------------
7 7/8% Notes Due May 15, 2043............. $105,000,000 $122,482,500 $15,519(1)(3)
- ---------------------------------------------------------------------------------------------------------------------------------
Guarantee of the 9 3/4% Notes Due June 15,
2020.................................... $231,000,000 N/A (4)
- ---------------------------------------------------------------------------------------------------------------------------------
Guarantee of the 7 7/8% Notes Due May 15,
2043.................................... $105,000,000 N/A (4)
- ---------------------------------------------------------------------------------------------------------------------------------
- ---------------------------------------------------------------------------------------------------------------------------------
</Table>

(1) Estimated solely for the purpose of computing the registration fee in
accordance with Rule 457(f) under the Securities Act based on 42% of the
outstanding principal amount of 9 3/4% Debentures of Consolidated Rail
Corporation, or "Conrail," due June 15, 2020 ($231,000,000) and of 7 7/8%
Debentures of Conrail due May 15, 2043 ($105,000,000), multiplied by the
average of the bid and ask market price on April 20, 2004 for each of the
9 3/4% Debentures of Conrail (135%) and each of the 7 7/8% Debentures of
Conrail (117%), respectively, represented in each case as a percentage of
par, less an amount equal to 42% of the aggregate cash payment to be paid
for each of the 9 3/4% Debentures of Conrail ($7.00 per $1,000 principal
amount of such 9 3/4% Debentures) and for each of the 7 7/8% Debentures of
Conrail ($7.50 per $1,000 principal amount of such 7 7/8% Debentures)
validly tendered in the exchange offer and consent solicitation assuming
100% of the Debentures of Conrail are validly tendered and accepted for
exchange in such exchange offer and consent solicitation.
(2) Exclusive of accrued interest, if any.
(3) Fee previously paid.
(4) The 9 3/4% Notes and the 7 7/8% Notes to be issued by NYC Newco, Inc. will
be guaranteed by CSX Transportation, Inc. Pursuant to Rule 457(n), no
separate fee is required to be paid in respect of the guarantees of the
9 3/4% Notes or the 7 7/8% Notes which are being registered concurrently.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

ITEM 21. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES

<Table>
<Caption>
PAGE NUMBER OR
EXHIBIT INCORPORATION BY
NO. DESCRIPTION REFERENCE TO
- ------- --------------------------------------------------------- ---------------------------

2.1 Form of Distribution Agreement by and among CSX Previously filed.
Corporation, CSX Transportation, Inc., CSX Rail Holding
Corporation, CSX Northeast Holding Corporation, New York
Central Lines LLC, Norfolk Southern Corporation, Norfolk
Southern Railway Company, Pennsylvania Lines LLC, Conrail
Inc., Green Acquisition Corp., Consolidated Rail
Corporation, CRR Holdings LLC, NYC Newco, Inc. and PRR
Newco, Inc.
2.2 Form of Transaction Agreement Amendment by and among CSX Previously filed.
Corporation, CSX Transportation, Inc., Norfolk Southern
Corporation, Norfolk Southern Railway Company, Conrail
Inc., Consolidated Rail Corporation and CRR Holdings LLC.
2.3 Form of Tax Allocation Agreement by and among Green Previously filed.
Acquisition Corp., Conrail, Inc., Consolidated Rail
Corporation, Pennsylvania Lines LLC and New York Central
Lines LLC.
3.1 Amended and Restated Articles of Incorporation of CSX Incorporated by reference
Transportation, Inc. to Exhibit 3.1 to CSX
Transportation, Inc.'s
Annual Report on Form 10-K
for the fiscal year ended
December 29, 1995, filed
with the SEC on March 8,
1996.
3.2 Bylaws, as amended, of CSX Transportation, Inc. Incorporated herein by
reference to Exhibit 3.2 to
CSX Transportation, Inc.'s
Annual Report on Form 10-K
for the fiscal year ended
December 26, 2003, filed
with the SEC on March 10,
2004.
3.3 Articles of Incorporation of NYC Newco, Inc. Previously filed.
3.4 Bylaws of NYC Newco, Inc. Previously filed.
4.1 Form of Indenture for Senior Securities, by and among NYC Filed herewith.
Newco, Inc., as Issuer, CSX Transportation, Inc., as
Guarantor, and The Bank of New York, as Trustee.
4.2 Form of 9 3/4% Global Note due 2020. Previously filed.
4.3 Form of 7 7/8% Global Note due 2043. Previously filed.
4.4 In accordance with Item 601(b)(4)(iii) of Regulation S-K, N/A
copies of instruments of CSXT and its subsidiaries with
respect to the rights of holders of long-term debt not
being registered herein are not filed herewith, or
incorporated by reference, but will be furnished to the
Commission upon request.
5.1 Opinion of Wachtell, Lipton, Rosen & Katz, special Previously filed.
counsel to CSX Transportation, Inc. and NYC Newco, Inc.
12.1 Computation of Ratio of Earnings to Fixed Charges for CSX Previously filed.
Transportation, Inc. and Subsidiaries.
23.1 Consent of Ernst & Young LLP. Previously filed.
23.2 Consent of Ernst & Young LLP and KPMG LLP, independent Previously filed.
registered public accounting firms.
</Table>

II-1

<Table>
<Caption>
PAGE NUMBER OR
EXHIBIT INCORPORATION BY
NO. DESCRIPTION REFERENCE TO
- ------- --------------------------------------------------------- ---------------------------

23.3 Consent of Wachtell, Lipton, Rosen & Katz. Included in Exhibit 5.1.
24.1 Powers of Attorney. Previously filed.
25.1 Statement of Eligibility and Qualification on Form T-1 of Previously filed.
The Bank of New York, as trustee under the Indenture for
the 9 3/4% Notes due 2020 and the 7 7/8% Notes due 2043.
99.1 Form of Letter of Consent/Transmittal. Filed herewith.
99.2 Form of Notice of Guaranteed Delivery. Filed herewith.
99.3 Form of Client Letter. Filed herewith.
99.4 Form of Letter to Brokers, Dealers, Commercial Banks, Filed herewith.
Trust Companies and Other Nominees.
99.5 Guidelines for Certification of Taxpayer Identification Previously filed.
Number on Substitute Form W-9.
99.6 Indenture, dated as of May 1, 1990, between Consolidated Previously filed.
Rail Corporation and J.P. Morgan Trust Company, National
Association, as successor to Bank One Trust Company,
N.A., a national banking corporation, which was successor
in interest to The First National Bank of Chicago, a
national banking association.
99.7 Conrail Supplemental Indenture, dated as of August 25, Previously filed.
1998, between Consolidated Rail Corporation and J.P.
Morgan Trust Company, National Association, as successor
to Bank One Trust Company, N.A., a national banking
corporation, which was successor in interest to The First
National Bank of Chicago, a national banking association.
</Table>

II-2

SIGNATURES

Pursuant to the requirements of the Securities Act, the Registrant has duly
caused this registration statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of Jacksonville, State of
Florida, on this 9th day of August, 2004.

CSX TRANSPORTATION, INC.

By: /s/ CAROLYN T. SIZEMORE
------------------------------------
Name: Carolyn T. Sizemore
Title: Vice-President and Controller

NYC NEWCO, INC.

By: /s/ CAROLYN T. SIZEMORE
------------------------------------
Name: Carolyn T. Sizemore
Title: Vice-President and
Controller

Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the dates indicated.

<Table>
<Caption>
SIGNATURE TITLE DATE
--------- ----- ----

* Chairman of the Board, President August 9, 2004
- ------------------------------------------------ and Chief Executive Officer of CSX
Michael J. Ward Transportation, Inc. (Principal
Executive Officer)

* Executive Vice President, Chief August 9, 2004
- ------------------------------------------------ Financial Officer and Director of
Oscar Munoz CSX Transportation, Inc.
(Principal Financial Officer)

/s/ CAROLYN T. SIZEMORE Vice President and Controller of August 9, 2004
- ------------------------------------------------ CSX Transportation, Inc.
Carolyn T. Sizemore (Principal Accounting Officer)

* Director of CSX Transportation, August 9, 2004
- ------------------------------------------------ Inc.
Clarence W. Gooden

* President of NYC Newco, Inc. August 9, 2004
- ------------------------------------------------ (Principal Executive Officer)
Ellen M. Fitzsimmons

/s/ CAROLYN T. SIZEMORE Vice President and Controller of August 9, 2004
- ------------------------------------------------ NYC Newco, Inc. (Principal
Carolyn T. Sizemore Accounting Officer)
</Table>

II-3

<Table>
<Caption>
SIGNATURE TITLE DATE
--------- ----- ----

* Vice President and Director of NYC August 9, 2004
- ------------------------------------------------ Newco, Inc. (Principal Financial
David A. Boor Officer)

* Vice President and Director of NYC August 9, 2004
- ------------------------------------------------ Newco, Inc.
Peter J. Shudtz

* Vice President and Director of NYC August 9, 2004
- ------------------------------------------------ Newco, Inc.
Nathan D. Goldman

*By: /s/ CAROLYN T. SIZEMORE
------------------------------------------
Carolyn T. Sizemore
Attorney-in-fact
Dated: August 9, 2004
</Table>

II-4

EXHIBIT INDEX

<Table>
<Caption>
PAGE NUMBER OR
EXHIBIT INCORPORATION BY
NO. DESCRIPTION REFERENCE TO
- ------- --------------------------------------------------------- ---------------------------

25.1 Statement of Eligibility and Qualification on Form T-1 of Previously filed.
The Bank of New York, as trustee under the Indenture for
the 9 3/4% Notes due 2020 and the 7 7/8% Notes due 2043.
99.1 Form of Letter of Consent/Transmittal. Filed herewith.
99.2 Form of Notice of Guaranteed Delivery. Filed herewith.
99.3 Form of Client Letter. Filed herewith.
99.4 Form of Letter to Brokers, Dealers, Commercial Banks, Filed herewith.
Trust Companies and Other Nominees.
99.5 Guidelines for Certification of Taxpayer Identification Previously filed.
Number on Substitute Form W-9.
99.6 Indenture, dated as of May 1, 1990, between Consolidated Previously filed.
Rail Corporation and J.P. Morgan Trust Company, National
Association, as successor to Bank One Trust Company,
N.A., a national banking corporation, which was successor
in interest to The First National Bank of Chicago, a
national banking association.
99.7 Conrail Supplemental Indenture, dated as of August 25, Previously filed.
1998, between Consolidated Rail Corporation and J.P.
Morgan Trust Company, National Association, as successor
to Bank One Trust Company, N.A., a national banking
corporation, which was successor in interest to The First
National Bank of Chicago, a national banking association.
</Table>