The Hudson Subdivision is a railroad line owned by CSX Transportation and leased by Amtrak in the U.S. state of New York. The line runs from Hyde Park north along the east shore of the Hudson River to Rensselaer and northwest to Scotia via Albany and Schenectady along a former New York Central Railroad line. From its south end, CSX has trackage rights south to New York City along the Metro-North Railroad's Hudson Line. The Hudson Subdivision junctions the Schodack Subdivision in Stuyvesant, Amtrak's Post Road Branch in Rensselaer, and the Carman Subdivision in Schenectady. Its northwest end is at a merge with the Selkirk Subdivision.
Amtrak's Empire Service, Lake Shore Limited, and Maple Leaf operate over the entire Hudson Subdivision; the Adirondack and Ethan Allen Express use the line southeast of the Delaware and Hudson Railway junction in Schenectady. The trackage west of that junction is owned by Amtrak and used by CSX via trackage rights.
The Mohawk and Hudson Railroad opened a line from Albany to Schenectady in 1831. The Utica and Schenectady Railroad opened from Schenectady west to Utica in 1836, including the present Hudson Subdivision west of Schenectady. On the east side of the Hudson River, the Hudson River Railroad opened from New York City north to Rensselaer in 1851. The original Hudson River crossing was the Hudson River Bridge, but the Livingston Avenue Bridge, the current crossing, opened in 1902. The entire line became part of the New York Central, later Penn Central, and finally Conrail, through leases, mergers, and takeovers. The line was then assigned to CSX in the 1999 breakup of Conrail.
In October 2011, CSX and Amtrak reached an agreement for Amtrak to lease the line between Poughkeepsie and Schenectady, with Amtrak assuming maintenance and capital responsibilities. CSX will retain freight rights over the line, which hosts only five freights a day. Amtrak will use federal funds to double track the line between Rennselaer and Schenectady, and add an additional station track at the Albany-Rennsalaer station. Amtrak sees the lease as key to improving Empire Service speeds and frequencies. Amtrak officially assumed control on December 1, 2012, with trains in the section now dispatched by the Amtrak Control and Command Center in New York City.
- "Governor Cuomo Announces Hudson Rail Lease - Amtrak/CSX Deal Will Improve Passenger Service, Move Projects Forward" (PDF) (Press release). Albany, New York: Amtrak. 2012-12-04. Retrieved 2012-12-05.
- CSX Timetables: Hudson Subdivision
- "PRR Chronology, 1831" (PDF). (70.4 KiB), June 2004 Edition
- "PRR Chronology, 1836" (PDF). (93.3 KiB), June 2004 Edition
- "PRR Chronology, 1851" (PDF). (67.7 KiB), March 2005 Edition
- "6) Livingston Avenue Bridge Rehabilitation". Capital District Transportation Committee. Archived from the original on 2008-05-16. Retrieved 2009-06-11.
- Eric Anderson (October 18, 2011). "Amtrak leasing track corridor". Times-Union. Retrieved October 25, 2011.