The Capital Subdivision is a

railroad Rail transport (also known as train transport) is a means of transport using wheeled vehicles running in railway track, tracks, which usually consist of two parallel steel railway track, rails. Rail transport is one of the two primary means of ...

line owned and operated by

CSX Transportation CSX Transportation , known colloquially as simply CSX, is a Class I freight railroad company operating in the Eastern United States and the Canadian provinces of Ontario and Quebec. Operating about 21,000 route miles () of track, it is the lead ...

in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

Maryland Maryland ( ) is a U.S. state, state in the Mid-Atlantic (United States), Mid-Atlantic region of the United States. It borders the states of Virginia to its south, West Virginia to its west, Pennsylvania to its north, and Delaware to its east ...

and the

District of Columbia Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and Federal district of the United States, federal district of the United States. The city is on the Potomac River, across from ...

. The line runs from near

Baltimore Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...

, Maryland, southwest to

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

, along the former Baltimore and Ohio Rail Road (B&O) Washington Branch. The subdivision's Alexandria Extension provides a connection to

Virginia Virginia, officially the Commonwealth of Virginia, is a U.S. state, state in the Southeastern United States, Southeastern and Mid-Atlantic (United States), Mid-Atlantic regions of the United States between the East Coast of the United States ...

and points south.

Route description

The northeast end of the line is at Halethorpe, Maryland, (BAA 5.8) 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 The yard (symbol: yd) is an English units, English unit of length in both the British imperial units, imperial and US United States customary units, customary systems of measurement equalling 3 foot (unit), feet or 36 inches. Sinc ...

north of

Washington Union Station Washington Union Station, known locally as Union Station, is a major train station, transportation hub, and leisure destination in Washington, D.C. Designed by Daniel Burnham and opened in 1907, it is Amtrak's second-busiest station and North ...

, at a junction with the

Metropolitan Subdivision The Metropolitan Subdivision is a railroad line owned and operated by CSX Transportation in Washington, D.C. and Maryland. The 53-mile line runs from Washington, D.C., northwest to Weverton, Maryland, along the former Metropolitan Branch of ...

and

Amtrak The National Railroad Passenger Corporation, Trade name, doing business as Amtrak (; ), is the national Passenger train, passenger railroad company of the United States. It operates intercity rail service in 46 of the 48 contiguous United Stat ...

Northeast Corridor The Northeast Corridor (NEC) is an electrified railroad line in the Northeast megalopolis of the United States. Owned primarily by Amtrak, it runs from Boston in the north to Washington, D.C., in the south, with major stops in Providence, Rhod ...

. Between Elkridge and Laurel (BAA 21.7), the Capital Subdivision's rail alignment forms the border between

Howard Howard is a masculine given name derived from the English surname Howard. ''The Oxford Dictionary of English Christian Names'' notes that "the use of this surname as a christian name is quite recent and there seems to be no particular reason for ...

and Anne Arundel counties, having been built before Howard County was created from western Anne Arundel County in 1844. MARC Train's

Camden Line The Camden Line is a MARC commuter rail line that runs for between Washington Union Station in Washington, D.C., and Camden Station in Baltimore, Maryland, over the CSX Capital Subdivision and Baltimore Terminal Subdivision. The Baltimor ...

, descended from B&O commuter service between Baltimore and Washington, operates over the entire length of the main line.

History

In 1831, the

Maryland General Assembly The Maryland General Assembly is the state legislature of the U.S. state of Maryland that convenes within the State House in Annapolis. It is a bicameral body: the upper chamber, the Maryland Senate, has 47 representatives, and the lower ...

authorized the B&O to build a branch from their main line within of

, to

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 A relay Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts An automotive-style miniature relay with the dust cover taken off A relay is an electrically operated switc ...

, roughly from Baltimore. Notable structural features on the original line include the Thomas Viaduct, the first multi-span

masonry Masonry is the craft of building a structure with brick, stone, or similar material, including mortar plastering which are often laid in, bound, and pasted together by mortar (masonry), mortar. The term ''masonry'' can also refer to the buildin ...

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 Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...

truss bridge A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements, usually forming triangular units. The connected elements, typically straight, may be stressed from tension, compression, or ...

Washington, D.C. depots

The first B&O passenger station (1835–1851) was located west of the Capitol, at 2nd Street and

Pennsylvania Avenue Pennsylvania Avenue is a primarily diagonal street in Washington, D.C. that connects the United States Capitol with the White House and then crosses northwest Washington, D.C. to Georgetown (Washington, D.C.), Georgetown. Traveling through So ...

NW. In 1851, the New Jersey Avenue 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 A street running train is a train which runs on a Railway track, track built on public streets. The rails are embedded in the roadway, and the train shares the street with other users, such as pedestrians, cars and cyclists, thus often being ref ...

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

in 1907, that alignment was changed to the current routing, partially using the former location of Delaware Avenue.

Acquisition

The

Chesapeake and Ohio Railway The Chesapeake and Ohio Railway was a Class I railroad formed in 1869 in Virginia from several smaller Virginia railroads begun in the 19th century. Led by industrialist Collis Potter Huntington, it reached from Virginia's capital city of Rich ...

acquired control of the B&O in 1962, and the B&O and C&O both became a subsidiaries of the

Chessie System Chessie System, Inc. was a holding company that owned the Chesapeake and Ohio Railway (C&O), the Baltimore and Ohio Railroad (B&O), the Western Maryland Railway (WM), and Baltimore and Ohio Chicago Terminal Railroad (B&OCT). Trains operated u ...

in 1973 (Along with the

Western Maryland Railway The Western Maryland Railway was a small American Class I railroad (1852–1983) that operated in 3 Southern United States, Southern US States, Maryland (Western Maryland, Western Region), West Virginia (Potomac Highlands of West Virginia, Easte ...

). In 1980 the Chessie System merged with the Seaboard System to form

CSX Corporation CSX Corporation is an American holding company focused on rail transportation and real estate in North America, among other industries. The company was established in 1980 as part of the Chessie System and Seaboard Coast Line Industries merge ...

. In 1987 the CSX Corporation merged the B&O into the C&O, then, later that same year, merged the C&O into

(CSXT), which now owns the line.

References

External links