Main line (railway)
The main line or mainline (American English) of a railway is a track that is used for through trains or is the principal artery of the system from which branch lines, yards, sidings and spurs are connected. There is no official definition; if the railroad calls a line a "main line" then it's a main line.
It generally refers to a route between towns, as opposed to a route providing suburban or metro services. For capacity reasons, main lines in many countries have at least a double track and often more than two parallel tracks.
Main line tracks typically allow higher speeds than branch lines and are built and maintained to a higher standard than yards and branch lines.
Railway points (railroad switches in the US) are usually set in the direction of the main line by default. Failure to do so has been a factor in several fatal railway accidents, for example the Buttevant Rail Disaster in Ireland,[1] and the Graniteville train disaster in the US.[2]
Main lines may also be operated under shared access by a number of railway companies, with sidings and branches operated by private companies or single railway companies.
In the UK, the term "main line" may also be used to distinguish any train or track that is not part of a light-rail or underground network.
References
- ^ "Report of the Investigation into the Accident on the CIE Railway at Buttevant, Co. Cork, on 1st August, 1980" (PDF). Department of Transport. April 1981. p. 31. Retrieved 2007-12-05.
- ^ United States National Transportation Safety Board (November 29, 2005). "Report of Railroad Accident: Collision of Norfolk Southern Freight Train 192 with Standing Norfolk Southern Local Train P22 With Subsequent Hazardous Materials Release. Graniteville, South Carolina; January 6, 2005. NTSB/RAR-05/04" (PDF). Retrieved 2005-11-29.