|MARC Brunswick Line|
The station depot at Boyds station along the Brunswick line, seen in July 2012 from the station parking lot.
|Type||Commuter rail line|
|System||MARC Commuter Rail|
|Locale||Washington D.C. and northern Maryland surburbs; West Virginia|
|Termini||Washington D.C. Union Station
|Owner||CSX Transportation (tracks)|
|Operator(s)||Bombardier Transportation/Maryland Transit Administration|
|Track gauge||4 ft 8 1⁄2 in (1,435 mm)|
The Brunswick Line is a MARC commuter rail line consisting of a main line running from Washington D.C. to Martinsburg, West Virginia and a branch line from just south of Point-of-Rocks station to Frederick, Maryland. The service is operated under contract by CSX Transportation, but is administered by MARC, a service of the Maryland Transit Administration (MTA). The Brunswick Line is MARC's longest line, and operates over CSX's Metropolitan, Old Main Line, and Cumberland Subdivisions. It is the successor to commuter services provided by the Baltimore & Ohio Railroad (B&O) as long ago as the mid-19th century. In 1971, Amtrak acquired passenger service from the B&O and established the Blue Ridge service in 1973. In 1983, Maryland, along with a number of other Northeastern states, took control of its commuter railroads and the "MARC" (Maryland Area Regional Commuter) service name was established. The Brunswick Line was not acquired from Amtrak until 1986.
The Brunswick Line (like the Camden Line) is a diesel-only line. All trains are usually 3 to 6 cars long with usually a single diesel locomotive in push-pull configuration however some trains like 880 or 883 can operate 2 locomotives from time to time, (with cab-car end towards Union Station). The line uses a mix of single level cars and bilevels for every train except 874 and 875 . The Brunswick Line is the only line to utilize ex-Metra Pullman Gallery cars, since it's the only MARC line to use all low-level platforms on the main line between Martinsburg and Washington D.C. These gallery cars are normally seen on 874/875 but when MARC gets the new Bombardier Multilevel II Cars, they will be replacing the old ex-Metra pullman cars. However, gallery cars are restricted from the Frederick Branch due to Monocacy station having a high platform.
There are 9 total inbound and 9 outbound trains to/from Union Station on a normal weekday. On Fridays, there is an additional outbound train. 3 trains in each direction service the Frederick branch. The rest continue to/from Brunswick, with 5 inbounds and 3 outbounds going all the way to/from Martinsburg. Meet-the-MARC Shuttle Bus connects Frederick with all trains that do not service Frederick directly (via Point of Rocks).
Amtrak's Capitol Limited, which runs daily in both directions between Chicago and Washington, D.C., uses the same trackage as the Brunswick Line and shares stations with MARC at Martinsburg, Harpers Ferry, Rockville, and Union Station. Connections are also available to the Washington Metro Red Line at Rockville, Silver Spring, and Union stations.
Trains were operated by CSX Transportation, although MARC announced in early May 2010 that it planned to find a new operator for the line, as well as for the Camden Line after CSX announced its desire to leave the business of operating commuter trains. Operating and maintenance responsibility for the Camden and Brunswick Lines was transferred from CSXT to Bombardier Transportation Services USA Corporation (BTS), a subsidiary of the Canadian company Bombardier Transportation, effective 12:01 a.m. on June 29, 2013. BTS crews started operating MARC trains on Monday, July 1, 2013. CSXT continues to dispatch MARC Camden and Brunswick Line trains after transition on behalf of the MTA. 
The following station stops are made by Brunswick Line trains; not all trains make all stops.
- MTA Average Weekday Ridership - by Month Retrieved 2013-07-25.
- Reynolds, Kirk; Dave Oroszi (2000). Baltimore & Ohio Railroad. Osceola, WI: MBI. p. 126. ISBN 0760307466. OCLC 42764520.
- MARC History on MTA website[dead link]
- Template:Https://mta.maryland.gov/sites/default/files/Brunswick Jan2013.pdf
- "MARC to seek new operator for CSX-run routes". Trains Magazine. 14 June 2010. Retrieved 14 June 2010.
- Weir, Kytja (17 October 2012). "Bombardier wins $204m MARC commuter train contract". The Washington Examiner. Retrieved 28 October 2012.
- Station was to have been closed because of low ridership per early-2006 MARC plan that was ultimately canceled.