Commuter rail in the context of Altamont Corridor Express

Inter-city rail services are express trains that run services that connect cities over longer distances than commuter or regional trains. They include rail services that are neither short-distance commuter rail trains within one city area nor slow regional rail trains stopping at all stations and covering local journeys only. An inter-city train is typically an express train with limited stops and comfortable carriages to serve long-distance travel.

Inter-city rail sometimes provides international services. This is most prevalent in Europe because of the proximity of its 50 countries to a 10,180,000-square-kilometre (3,930,000-square-mile) area. Eurostar and EuroCity are examples. In many European countries, the word InterCity or Inter-City is an official brand name for a network of regular-interval and relatively long-distance train services that meet certain criteria of speed and comfort. That use of the term appeared in the United Kingdom in the 1960s and has been widely imitated.

Shinjuku Station (新宿駅, Shinjuku-eki) is a major railway station in Tokyo, Japan, that serves as the main connecting hub for rail traffic between central/eastern Tokyo (the special wards) and Western Tokyo on the inter-city rail, commuter rail, and subway lines. The station straddles the boundary between the Shinjuku and Shibuya special wards. In Shinjuku, it is in the Nishi-Shinjuku and Shinjuku districts; in Shibuya, it is in the Yoyogi and Sendagaya districts.

The station was used by an average of 3.59 million people per day in 2018, making it the world's busiest railway station by far (and registered as such with Guinness World Records). The main East Japan Railway Company (JR East) station and the directly adjacent private railways have a total of 35 platforms, an underground arcade, above-ground arcade and numerous hallways with another 17 platforms (52 total) that can be accessed through hallways to five directly connected stations without surfacing outside. The entire above/underground complex has well over 200 exits.

Nassau County (/ˈnæsɔː/ NASS-aw) is a suburban county located on Long Island, immediately to the east of New York City, bordering the Long Island Sound on the north and the open Atlantic Ocean to the south. As of the 2020 United States census, Nassau County's population was 1,395,774, making it the sixth-most populous county in the State of New York, and reflecting an increase of 56,242 (+4.2%) from the 1,339,532 residents enumerated at the 2010 census. Its county seat is Mineola, while the county's largest and most populous town is Hempstead.

Situated on western Long Island, the County of Nassau borders New York City's borough of Queens to its west, and Long Island's Suffolk County to its east. It is the most densely populated and second-most populous county in the State of New York outside of New York City, with which it maintains extensive rail and highway connectivity, and is considered one of the central counties within the New York metropolitan area.

30th Street Station, officially William H. Gray III 30th Street Station, is a major intermodal transit station in Philadelphia, Pennsylvania, United States. The station opened in 1933 as Pennsylvania Station–30th Street, replacing the 1881 Broad Street station as the Pennsylvania Railroad's main station in the city. The station is the third-busiest Amtrak station in the nation with over 4.1 million passengers as of 2023.

30th Street Station is currently metropolitan Philadelphia's main railroad station and a major stop on Amtrak's Northeast and Keystone corridors. The station is also a major commuter rail station served by all SEPTA Regional Rail lines and is the western terminus for NJ Transit's Atlantic City Line. The station is also served by several SEPTA-managed city and suburban buses and by NJ Transit, Amtrak Thruway, and various intercity operators.

Regional rail is a public rail transport service that operates between towns and cities. These trains operate with more stops than inter-city rail, and unlike commuter rail, operate beyond the limits of urban areas, connecting smaller cities and towns.

In North America, "regional rail" is often used as a synonym for "commuter rail", while in other places "commuter rail" refers to systems that primarily or only offer service during rush hour while "regional rail" refers to systems that offer all-day service. In Europe, regional trains have their own category, often abbreviated to R (RB in Germany) or L (for local train).

In public transit, particularly bus, tram, or train transportation, a limited-stop (or sometimes referred to as semi-fast) service is a trip pattern that stops less frequently than a local service. Many limited-stop or semi-fast services are a combination of commuter rail and express train.

The term is normally used on routes with a mixture of fast and slow services, and can differ in meaning, depending on how it is used by different transit agencies. The main benefits of limited-stop or semi-fast services is the ability to utilise skip-stop calling pattern to maximise capacity along the line, as opposed to a commuter service stopping at every station which slows trailing express trains down.

An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or on-board energy storage such as a battery or a supercapacitor. Locomotives with on-board fuelled prime movers, such as diesel engines or gas turbines, are classed as diesel–electric or gas turbine–electric and not as electric locomotives, because the electric generator/motor combination serves only as a power transmission system.

Electric locomotives benefit from the high efficiency of electric motors, often above 90% (not including the inefficiency of generating the electricity). Additional efficiency can be gained from regenerative braking, which allows kinetic energy to be recovered during braking to put power back on the line. Newer electric locomotives use AC motor-inverter drive systems that provide for regenerative braking. Electric locomotives are quiet compared to diesel locomotives since there is no engine and exhaust noise and less mechanical noise. The lack of reciprocating parts means electric locomotives are easier on the track, reducing track maintenance. Power plant capacity is far greater than any individual locomotive uses, so electric locomotives can have a higher power output than diesel locomotives and they can produce even higher short-term surge power for fast acceleration. Electric locomotives are ideal for commuter rail service with frequent stops. Electric locomotives are used on freight routes with consistently high traffic volumes, or in areas with advanced rail networks. Power plants, even if they burn fossil fuels, are far cleaner than mobile sources such as locomotive engines. The power can also come from low-carbon or renewable sources, including geothermal power, hydroelectric power, biomass, solar power, nuclear power and wind turbines. Electric locomotives usually cost 20% less than diesel locomotives, their maintenance costs are 25–35% lower, and cost up to 50% less to run.

Headway is the distance or duration between vehicles in a transportation system. The minimum headway is the shortest such distance or time achievable by a system without a reduction in the speed of vehicles. The precise definition varies depending on the application, but it is most commonly measured as the distance from the tip (front end) of one vehicle to the tip of the next one behind it. It can be expressed as the distance between vehicles, or as time it will take for the trailing vehicle to cover that distance. A "shorter" headway signifies closer spacing between the vehicles. Airplanes operate with headways measured in hours or days, freight trains and commuter rail systems might have headways measured in parts of an hour, metro and light rail systems operate with headways on the order of 90 seconds to 20 minutes, and vehicles on a freeway can have as little as 2 seconds headway between them.

Headway is a key input in calculating the overall route capacity of any transit system. A system that requires large headways has more empty space than passenger capacity, which lowers the total number of passengers or cargo quantity being transported for a given length of line (railroad or highway, for instance). In this case, the capacity has to be improved through the use of larger vehicles. On the other end of the scale, a system with short headways, like cars on a freeway, can offer relatively large capacities even though the vehicles carry few passengers.

Grand Central Terminal (GCT; also referred to as Grand Central Station or simply as Grand Central) is a commuter rail terminal at 42nd Street and Park Avenue in Midtown Manhattan, New York City. Grand Central is the southern terminus of the Metro-North Railroad's Harlem, Hudson and New Haven Lines, serving the northern parts of the New York metropolitan area. It also serves the Long Island Rail Road through Grand Central Madison, a 16-acre (65,000 m) addition to the station located underneath the Metro-North tracks, built from 2007 to 2023. The terminal also connects to the New York City Subway at Grand Central–42nd Street station. The terminal is the third-busiest train station in North America, after New York Penn Station and Toronto Union Station.

The distinctive architecture and interior design of Grand Central Terminal's station house have earned it several landmark designations, including as a National Historic Landmark. Its Beaux-Arts design incorporates numerous works of art. Grand Central Terminal is one of the world's ten most-visited tourist attractions, with 21.6 million visitors in 2018, excluding train and subway passengers. The terminal's Main Concourse is often used as a meeting place, and is especially featured in films and television. Grand Central Terminal contains a variety of stores and food vendors, including upscale restaurants and bars, a food hall, and a grocery marketplace. The building is also noted for its library, event hall, tennis club, control center and offices for the railroad, and sub-basement power station.

Pennsylvania Station (also known as New York Penn Station or simply Penn Station) is the main intercity railroad station in New York City and the busiest transportation facility in the Western Hemisphere, serving more than 600,000 passengers per weekday as of 2019. The station is located beneath Madison Square Garden in the block bounded by Seventh and Eighth Avenues and 31st and 33rd Streets and in the James A. Farley Building, with additional exits to nearby streets, in Midtown Manhattan. It is close to several popular Manhattan locations, including Herald Square, the Empire State Building, Koreatown, and Macy's Herald Square.

Penn Station has 21 tracks fed by seven tunnels, including its two North River Tunnels, four East River Tunnels, and one Empire Connection tunnel. It is at the center of the Northeast Corridor, a passenger rail line that connects New York City with Boston to its north and Philadelphia, Baltimore, and Washington, D.C. to its south, along with various intermediate stations. Intercity trains are operated by Amtrak, which owns the station, while commuter rail services are operated by the Long Island Rail Road (LIRR) and NJ Transit (NJT). Connections are available within the complex to the New York City Subway and buses.

Middlesex County is a county located in the north-central part of the U.S. state of New Jersey, extending inland from the Raritan Valley region to the northern portion of the Jersey Shore. As of the 2020 United States census, the county was the state's third-most populous county with a population of 863,162, its highest decennial count ever and an increase of 53,304 (+6.6%) from the 2010 census count of 809,858, which in turn reflected an increase of 59,696 (8.0%) from the 750,162 counted in the 2000 census. Middlesex is part of the New York metropolitan area. Many communities within the county serve as commuter towns to and from New York City and other points north. The county is part of the Central Jersey region of the state.

The county is located in the middle of the Northeast megalopolis of the U.S. Its county seat is the city of New Brunswick, a center for the sciences, arts, and cultural activities, and the headquarters of the state's flagship academic institution, Rutgers University. The county's most populous place, with 107,588 residents as of the 2020 census, is Edison, while Monroe Township covers the largest area of any municipality, at 42.19 square miles (109.3 km). Since the 2010 census, the state's center of population is in East Brunswick; the center of population for New Jersey has been in Middlesex County since the 1900 census. Middlesex County hosts an extensive transportation network, including several rail stations along the heavily traveled Northeast Corridor Line of the New Jersey Transit commuter rail system, as well as the intersection of the New Jersey Turnpike and the Garden State Parkway, the state's two busiest motor vehicle roadways, in Woodbridge Township. Middlesex County calls itself The Greatest County in the Land.

Trenton is the capital city of the U.S. state of New Jersey and the county seat of Mercer County. It was the capital of the United States from November 1 until December 24, 1784. Trenton and Princeton are the two principal cities of the Trenton–Princeton metropolitan statistical area, which encompasses all of Mercer County and constitutes part of the New York combined statistical area by the U.S. Census Bureau However, Trenton is part of the Philadelphia media market and directly borders the Philadelphia metropolitan area to its west, and the city was part of the Philadelphia combined statistical area from 1990 until 2000.

In the 2020 United States census, Trenton was the fifth largest city in Central Jersey and the 10th-most-populous municipality statewide, with a population of 90,871, an increase of 5,958 (+7.0%) from the 2010 census count of 84,913, which in turn had reflected a decline of 490 (−0.6%) from the 85,403 counted in the 2000 census. The Census Bureau's Population Estimates Program calculated that the city's population was 89,661 in 2022, ranking the city the 382nd-most-populous in the country. Trenton is the only city in New Jersey that is served by three commuter rail transit systems (Amtrak, NJ Transit, and SEPTA), and the city has encouraged a spate of transit-oriented development.

A park and ride, also known as incentive parking or a commuter lot, is a parking lot with public transport connections that allows commuters and other people heading to city centres to leave their vehicles and transfer to a bus, rail system (rapid transit, light rail, or commuter rail), or carpool for the remainder of the journey. The vehicle is left in the parking lot during the day and retrieved when the owner returns. Park and rides are generally located in the suburbs of metropolitan areas or on the outer edges of large cities. A park and ride that only offers parking for meeting a carpool and not connections to public transport may also be called a park and pool.

Park and ride is abbreviated as "P+R" on road signs in some countries, and is often styled as "Park & Ride" in marketing.

The Chase Line is a suburban railway line in the West Midlands region of England. It runs from its southern terminus, Birmingham New Street, to Walsall, and then Rugeley Trent Valley in Staffordshire, where it joins the Trent Valley line. The name of the line refers to Cannock Chase which it runs through at its northern end.

Part of the line, between Birmingham and Walsall, has been electrified since 1966; work to electrify the remaining 15 mile stretch of line between Walsall and Rugeley, was completed in December 2018.

The Réseau Express Régional (French pronunciation: [ʁezo ɛkspʁɛs ʁeʒjɔnal]; English: Regional Express Network), commonly abbreviated RER (pronounced [ɛʁəɛʁ]), is a hybrid commuter rail and rapid transit system serving the city centre of Paris and its suburbs. It acts as a combined city centre underground rail system and suburbs-to-city-centre commuter rail, similar to the S-Bahn in Germany, Austria and Switzerland, S-train in Copenhagen, the Pendeltåg in Sweden, the Overground and Elizabeth Line in London, S Lines in Milan, plus many other commuter rail networks around the world.

Conceived of as a métropolitain express ('express metro') during the mid-1930s, the scheme was revived in the 1950s and construction began in the early 1960s. The RER was not fully conceptualised until the completion of the Schéma directeur d'aménagement et d'urbanisme (rough translation: 'master plan for urban development') in 1965. The RER network, which initially comprised two lines, was formally inaugurated on 8 December 1977 in a ceremony that was attended by President Valéry Giscard d'Estaing. A second phase of construction commenced at the end of the 1970s which saw additional lines constructed along with extensions to the original two. The RER is operated partly by RATP, the authority that operates most of the public transport in Paris, and partly by the SNCF, France's national rail operator.

Dallas Area Rapid Transit (DART) is a transit agency serving the Dallas–Fort Worth metroplex of Texas. It operates buses, light rail, commuter rail, and high-occupancy vehicle lanes in Dallas and twelve of its suburbs. In 2024, the system had a ridership of 55,151,000, or about 162,900 per weekday as of the third quarter of 2025.

DART was created in 1983 to replace a municipal bus system and funded expansion of the region's transit network through a sales tax levied in member cities. DART rail began operation in 1996 and operates over 93 miles (149.7 km) of track. It was the longest light rail system in the United States until 2023, when it was surpassed by Los Angeles Metro Rail with the consolidation of the A Line.

The West Coast Main Line (WCML) is a significant railway corridor in the United Kingdom, which connects the major cities of London and Glasgow with branches to Birmingham, Manchester, Liverpool and Edinburgh. It is one of the busiest mixed-traffic railway routes in Europe, carrying a mixture of inter-city rail, regional rail, commuter rail and rail freight traffic. The core route of the WCML runs from London to Glasgow for 399 miles (642 km) and was opened between 1837 and 1881; this totals a route mileage of 700 miles (1,127 km) by including its many branches. The Glasgow–Edinburgh via Carstairs line connects the WCML to Edinburgh; however, the main London–Edinburgh route is the East Coast Main Line via York. Several sections of the WCML form part of the suburban railway systems in London, Coventry, Birmingham, Manchester, Liverpool and Glasgow, with many more smaller commuter stations, as well as providing links to more rural towns.

It is one of the busiest rail freight routes in Europe, carrying 40% of all UK traffic. The line is the principal rail freight corridor linking the European mainland (via the Channel Tunnel) through London and South East England to the West Midlands, North West England and Scotland. The line has been declared a strategic European route and designated a priority Trans-European Networks (TENS) route. A number of railway writers refer to it as "The Premier line".