Commuter rail

Commuter rail or suburban rail is a passenger rail service that primarily operates within a metropolitan area, connecting the central city to its suburbs and commuter towns. Commuter rail systems can use locomotive-hauled trains or multiple units, using electric or diesel propulsion. Distance charges or zone pricing may be used.

The term can refer to systems with a wide variety of different features and service frequencies, but typically refers to mainline rail services connecting suburban communities with central business districts over medium distances; it is distinguished from rapid transit systems, which operate inside the urban core.

Some services blur the line between suburban rail and rapid transit; examples include German S-Bahn in some cities, the Réseau Express Régional (RER) in Paris, the S Lines in Milan, many Japanese commuter systems, the East Rail line in Hong Kong, and some Australasian suburban networks, such as Sydney Trains and Metro Trains Melbourne. Many commuter rail systems share tracks with other passenger services and freight.

In North America, commuter rail sometimes refers only to systems that primarily operate during rush hour and offer little to no service for the rest of the day, with regional rail being used to refer to systems that offer all-day service.

Characteristics

Most commuter (or suburban) trains are built to main line rail standards, differing from light rail or rapid transit (metro rail) systems by:

being larger

providing more seating and less standing room, owing to the longer distances involved

having (in most cases) a lower frequency of service

having scheduled services (i.e., trains run at specific times rather than at specific intervals)

serving lower-density suburban areas, typically connecting suburbs to the city center

sharing track or right-of-way with intercity and/or freight trains

not fully grade separated (containing at-grade crossings with crossing gates)

being able to skip certain stations as an express service due to normally being driver-controlled

Train schedule

Compared to rapid transit (or metro rail), commuter/suburban rail often has lower frequency, following a schedule rather than running to a headway, and wider station spacing. Such services primarily serve lower-density suburban areas (outside the inner city), generally only having one or two stops in a city's central business district, and often share right-of-way with inter-city and freight trains. Often, service is concentrated in the peak, with fewer trains per hour running during the day; service late into the evening and on weekends may be reduced or not run at all.