Regional rail systems offer services to those who work in the Metropolitan area of big cities. They also provide connections between a central business district and suburbs. The development of regional rail services has become popular today, with the increased public awareness of many environmental issues, as well as the rising costs of owning and operating private vehicles.
The trains providing regional rail services are called commuter trains. They are optimized for maximum passenger volume, though they don't really have all the amenities of long-distance trains. Passenger coaches are either single- or double-level, with a capacity of 80 - 110 passengers for single-level cars and 145 - 170 for double-level cars. In some cases, a cross between a train and a metro has been created.
They run underground in the dense city centers and on ordinary outdoor tracks in lower-density areas. Since regional rail rides are usually within one or two hours, they cram as many passengers as possible. One frequently used seat plan is two rows of facing benches on the right and left sides of the train. It leaves much room for people who stand in the center. In the U.S. and other countries, a three-and-two seat plan is also used.Regional rail services mostly known as commuter rail services in the United States, Canada, and soon Mexico provide common passenger transportation along railway tracks, with scheduled service on fixed routes primarily for short-distance (local) travel between a central business district and adjacent suburbs. It does not include rapid transit or light rail service.
In the United States, inter-city and commuter trains are operated mostly by Amtrak over a network that is less dense than the ones in Europe or Japan. The most heavily used routes with the greatest schedule frequencies are in the Northeastern United States. Many commuter railways offer service during peak times only, and on a round-trip basis. Commuter trains are usually connected to metro or bus services at their destination as well as along the route.
Commuter trains are usually powered by locomotives. The motive power for locomotive-hauled commuter trains may be either electric or diesel-electric, although some countries, such as Germany and countries of the former Soviet-bloc also use diesel-hydraulic locomotives.
Most commuter rail services in North America are operated by government agencies. The 600 mile-long electrified Northeast Corridor in the United States is shared by commuter trains and Amtrak's Acela Express, regional, and intercity trains.
Merseyrail is the name given to the British electric commuter train network centered on Liverpool and Birkenhead. Merseyrail is one of the most frequent British commuter systems outside London. It transports 100,000 passengers a day with services running every 15 minutes during weekday daytime, and 30 minutes at evenings and weekends. Services run on two lines covering the Liverpool suburban area and greater Merseyside, with a total track length of 120 km and 67 stations.