Capital Subdivision

The Thomas Viaduct, built in 1835 over the Patapsco River, was the largest bridge in the United States at that time. It still carries the Capital Subdivision today and is the world's oldest multiple arched stone railroad bridge.

The Capital Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. state of Maryland and the District of Columbia. The line runs from near Baltimore, Maryland southwest to Washington, D.C. along the former Baltimore and Ohio Rail Road (B&O) Washington Branch. The subdivision's Alexandria Extension provides a connection to Virginia and points south.

Route description

Capital Subdivision
Legend
to Baltimore Terminal Subdivision BAA 5.8 Halethorpe / HX Tower(closed) to Old Main Line Subdivision BAA 6.7 Amtrak Northeast Corridor BAA 6.8 St. Denis BAA 9.0 Relay originally Washington Junction Thomas Viaduct over Patapsco River I-895 BAA 9.6 Elk Ridge BAA 11.6 Hanover BAA 13.4 Dorsey BAA 15.8 Jessup originally Jessup Cut Jessup Yard (East lead track) Waterloo Industrial Track Columbia Industrial Track Jessup Yard BAA 16.6 Annapolis Junction (defunct) Annapolis & Elk Ridge RR BAA 17.6 Fort Meade Junction BAA 18.1 Savage to Westbound storage track Corridor Industrial Track Savage Industrial Track x20px BAA 20.9 Laurel Race Track Patuxent River BAA 21.3 Laurel BAA 24.9 Muirkirk originally West Oak Bottom BAA 25.8 Ammendale BAA 26.9 Beltsville I-495 (Capital Beltway) BAA 29.0 Greenbelt BAA 30.0 Berwyn BAA 31.4 College Park originally Paint Branch BAA 32.4 Riverdale BAA 32.7 Riverdale Park Junction Alexandria Extension to RF&P Subdivision BAA 33.6 JD Tower(demolished) BAA 33.7 Hyattsville originally Bladensburg BAA 34.8 Brentwood BAA 37.0 F Tower to Metropolitan Subdivision BAA 37.7 C Tower K Tower(Amtrak) BAA 38.7 Washington
= flag stop

Main line

The northeast end of the line is at Halethorpe, Maryland, just north of the historic Thomas Viaduct, where it meets the Baltimore Terminal Subdivision and the Old Main Line Subdivision. Its southwest end is at the yard north of Union Station, at a junction with the Metropolitan Subdivision and Amtrak's Northeast Corridor.

Between Elkridge and Laurel, the Capital Subdivision's rail alignment forms the border between Howard and Anne Arundel counties, having been built before Howard County was created from western Anne Arundel County in 1844.

MARC Train's Camden Line provides passenger service over the entire length of the main line.

Alexandria Extension

The Alexandria Extension runs south 7.2 miles (11.6 km) from a junction at Hyattsville, Maryland to the Anacostia Railroad Bridge and the RF&P Subdivision in Southeast D.C. This busy route is used by freight trains to Virginia. It runs past Benning Yard and interchanges with the Landover Subdivision.

History

Main line

The Thomas Viaduct about 20 years after its construction in 1835

In 1831 the Maryland General Assembly authorized the B&O to build a branch from their main line within 8 miles (13 km) of Baltimore, to Washington. As this line would take much business from the parallel turnpikes, especially the Washington and Baltimore Turnpike, the charter specifically allowed those companies to subscribe to the stock of the railroad. Construction began in July 1833, and the line opened on August 25, 1835, splitting from the B&O main line at Relay, roughly 7 miles (11 km) from Baltimore.

Notable structural features on the original line include the Thomas Viaduct, the first multi-span masonry railroad bridge in the United States, and the largest bridge in the country when it was completed in 1835; and the earliest example of an iron truss bridge designed by Wendel Bollman and installed at Savage.  

Washington depots

Union Station in Washington, D.C.

The first B&O passenger station (1835–1852) was located west of the Capitol, at 2nd Street and Pennsylvania Avenue NW. In 1852 a new station was built at a point slightly north of the Capitol, on New Jersey Avenue NW, in the area now called Union Station Plaza. Trains reached that location via the current location of West Virginia Avenue, street-running trackage on I Street NE and Delaware Avenue, and private right-of-way just south of the current location of Louisiana Avenue. When the Washington Terminal Company opened the new Union Station in 1907, that alignment was changed to the current routing, partially using the former location of Delaware Avenue.

Alexandria Extension

Alexandria Extension
Legend
BAA 33.6 Capital Subdivision ← Washington • Baltimore → CFP 121.0 Apex of Wye Northeast Branch Anacostia River Baltimore-Washington Parkway CFP 119.2 Jones Hill US 50 Amtrak Northeast Corridor Landover Subdivision Washington Metro Maryland Washington, D.C. border CFP 117.2 Chesapeake Junction CFP 116.0 Benning Yard Landover Subdivision CFP 115.4 Shepherd Junction Shepherd Industrial Track DC 295 (Anacostia Freeway) CFP 114.8 Anacostia JunctionLandover Subdivision Anacostia Railroad Bridge over Anacostia River CFP 113.8 M Street RF&P Subdivision to Virginia

The Alexandria Extension, originally called the Alexandria Branch, was built in 1874 and ran 12.5 miles (20.1 km) to Shepherds Landing along the eastern shore of the Potomac River, to provide a connection to Virginia. The B&O had lost access to the Long Bridge across the river in 1870 due to political maneuvering by the Baltimore and Potomac Railroad (B&P)(controlled by the Pennsylvania Railroad (PRR)). In order to efficiently route its trains to points south of Washington, the B&O set up a car float operation at Shepherds Landing, which carried freight cars across the river to Alexandria, Virginia. The ferry operation was discontinued in 1906 when the B&O obtained trackage rights from PRR. The B&O built a connecting track from the Alexandria Extension to the B&P's Anacostia Railroad Bridge, which provided access to PRR tracks in southwest D.C. (now called the CSX RF&P Subdivision) and the Long Bridge.

During World War II, the B&O re-activated the Shepherds Landing crossing at the request of the U.S. Army. The Army had requested an additional Potomac River crossing for troop movements to supplement those on the Long Bridge, and the Corps of Engineers built a temporary bridge across the river in 1942. Both B&O and PRR trains traveled over the 3,360 foot (1,020 m) bridge. Train operations on the bridge ceased in 1945 at the end of the war, and the bridge was demolished in 1947.

For many years the junction at Hyattsville, called Alexandria Junction, was controlled by JD Tower. B&O built its first interlocking tower building at the site in 1894, and rebuilt the tower in 1912 and again in 1917. CSX closed this tower in 1992, and demolished it in 1994 after a fire.

The original track from the junction at Anacostia Bridge to Shepherds Landing became known as the Shepherd Branch. This spur served several industries, including Bolling Air Force Base and the Blue Plains Advanced Wastewater Treatment Plant. (Shown as "Shepherd Industrial Track" on the diagram.) The Blue Plains plant was the only customer on the branch when rail service ended in 2001.

Acquisition

The B&O became part of the Chesapeake and Ohio Railway in 1963 and the Chessie System in 1973. In 1980 Chessie became part of CSX, which now owns the line.

See also

• List of CSX Transportation lines

External links

• Mileposts from CSX Transportation Timetables
• Washington Branch Milestone Pictures
• JDTower.org - Photos and stories about JD Tower