Modes

Modes

Welcome to the Modes page here at the Metro Route Atlas! This page provides some brief descriptions on each mode. Click on icons below to jump to the mode.

Classifications can be highly blurred. As some terms lack a standard definition or have conflicting definitions depending on the country, it is impossible to be perfectly consistent when classifying systems across the entire world. We used to attempt to provide clear lines of separation between modes on this page, but this became unmaintainable due to differences between countries as well as the sheer number of hybrid systems. As a result, we will only post brief characteristics and will not use any hard numbers or cutoff points. The only exception to this is regards to frequency/headways, where we utilize the standard definition of 15 minute headways/4tph as our minimum definition of 'frequent'. We reserve the right to classify lines and systems however we want to on this website, regardless of system branding or local perception.

Note that on city pages, we use the term 'Rapid Transit' as a general term for high capacity and frequency modes (including the Metro, S-Trains, Light Rail, People Mover, and Gondola Lift categories, with some exceptions a.k.a. just Haifa). This usage is separate from the Metro mode. In addition, we have a three level classification system in use.

1. Mode - General type of line/service (e.g. Commuter Rail vs. People Mover)
2. Subcategory - Service and infrastructure style (e.g. Rapid Transit vs Light Metro; S-Train vs Urban Mainline Rail)
3. Variant Name - Technology or cultural style, or service/infrastructure style if not distinct enough to be a subcategory (e.g. VAL; Translohr; Straddle-Beam Monorail vs Suspension Railway)

In our Cities by Mode portals, we only show Mode (via the icon) and Subcategory. In city pages, we refer to lines and services by Variant Name (if one exists) and Subcategory.

We used to have 'Alternate Names' to refer to local naming schemes (e.g. RER, U-Bahn) but this was scrapped since this is an English language website, and supporting local naming schemes would have gotten out of hand. Instead, some subcategories have different options depending on the geographic/cultural region/country, but only when the alternative names are all commonly used in English. Only one of the options will be used except in cities by mode portals where a region uses multiple options (e.g. Tram/Streetcar in Canada due to English speaking parts using Streetcar and French speaking parts using Tram).

A note on mode classification can be found at the end of this page.

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But before talking about modes, some notes on how we handle the lines/services on this website:

• Line: Line refers to physical infrastructure. A physical line can have multiple services or service groupings running on it. We use Line as a primary classification method ONLY in Japan due to the way they handle through-services, and in cases where service is an inappropriate classification.
• Service: Service refers to a grouping of service patterns with a consistent brand. A service can run on multiple lines, or may correspond to exactly one line. If a service branches but the different service patterns can be grouped together under one label, we still refer to that as a service.
• Trunk Line: A Trunk Line refers to infrastructure upon which many services run, grouping different services together for convenience. For flexible systems such as busways, see Open Busway below.
• Network: We use Network when multiple services operate under a unified branding.

We also have some BRT-specific terminology for cases where it is difficult to describe the BRT system using only services (Note: For trunk and feeder systems, we use either Line or Service):

• Open Busway: An Open Busway refers to a portion of BRT infrastructure that is served by multiple services that continue beyond the busway as local routes. Open Busways may or may not have a primary local service - which is featured on our maps and pages is determined on a city by city basis. Some Open Busways do not have services that stop at all stations on the busway.

With that, you can use one of the icons below to navigate to the mode of your choice.

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The icon refers to grade separated Rapid Transit, including Metros, Subways, U-Bahn, T-Bahn, and all other aliases. Metro lines are characterized by high frequency, speed, and capacity. They also have both grade separation and separation from other modes for the entirety or vast majority of their routes. Service patterns are also typically simple, with only a few (typically just one or two) services servicing any given track at a platform. Due to their grade and mode separation and their tendency to run in a dedicated right of way, Metro systems are often automated, and newer systems may be built fully automated from the start.

Some services may have railway style grade crossings and/or share track with light rail or mainline services, but these are exceptions rather than the norm. Other Metro-grade corridors function as parts of Light Rail/Premetro or S-Train systems and are considered as such. Infrequent lines (headways of 20-30 minutes or worse off-peak) are considered Regional or Commuter Rail with a few exceptions.

Light Metro lines such as Automated Guideway Transit and Véhicule Automatique Léger (VAL) lines as well as Light Rapid Transit lines (such as in the ASEAN region) are also classified under the Metro label. Monorail, Suspension Railway, and Maglev lines are also included under the Metro label under the Light Metro subcategory unless they serve as short distance people movers. For the purposes of this site, only monorails used for meaningful mass transit are included - amusement park rides, private shuttles, and the like are not included. The Light Metro subcategory includes lines running with Light Rail Vehicles on a completely grade separated right of way.

Please note that the boundary between Light Metro (itself an ambiguously-defined term) and high capacity Metro is ill-defined. As of May 2021 we formally split the Light Metro grouping in two. We use (comparative) rolling stock size and maximum train length multiplied against car horizontal loading gauge as primary considerations when classifying between the Metro and MCS Metro subcategories, allowing rapid transit lines that use short heavy rail trainsets without the intention of increasing lengths to be considered Metro under the MCS Metro subcategory.

Subcategories:

• Metro - AKA Rapid Transit, U-Bahn, Subway, T-Bahn, etc. Base Definition. Examples: New York City Subway, Berlin U-Bahn, Shanghai Metro
• MCS Metro - AKA Medium Capacity (Rail) System, Light Rapid Transit, etc. Metro lines with heavy rail rolling stock in short (platforms built for a maximum of 3 cars) formations. Typically considered Light Metro in general discourse but we use Light Metro on this site to refer to rapid transit with lighter rolling stock. Examples: Taichung Metro
• Light Metro - AKA VAL, Automated Guideway Transit, etc. Metro lines purposefully built with medium capacity, but with high frequency and speed. Our definition considers lines using people mover, light rail, and lower capacity metro rolling stock even if train lengths result in equivalent or higher capacity than a standard Metro. Examples: Docklands Light Railway, Vancouver SkyTrain.

Light Metro Variants:

• High Floor LRV - Light Metro lines utilizing high floor light rail vehicle stock. Examples: Metrorrey Line 2, Istanbul Metro Line 1, Ankaray
• Low Floor LRV - Light Metro lines utilizing low floor tramway rolling stock. Examples: Changchun Metro Line 4, Vienna U-Bahn U6, Budapest Metro Line 1, Sevilla Metro
• VAL (Véhicule Automatique Léger) - French-origin Light Metro technology using rubber tyres. Examples: Lille Metro, Taipei Metro Brown Line
• Automated Guideway Transit - Non-VAL Light Metro technology using rubber tyres. Examples: Yurikamome, Port Island Line
• Straddle-Beam Monorail - Monorail lines straddling a single beam. Examples: Osaka Monorail, Tama Monorail
• Suspension Railway - AKA H-Bahn, etc. Lines suspended below a track. Examples: Wuppertal Schwebebahn, Chiba Monorail
• Maglev - Lines using magnetic levitation as a propulsion system. Examples: Linimo, Beijing Subway Line S1

External Definitions

American Public Transportation Association (Source)

For more information, refer to the following websites: List of Metro Systems (Wikipedia) | Rapid Transit (Wikipedia) | Medium-Capacity Rail System (Wikipedia) | Automated Guideway Transit (Wikipedia) | VAL (Wikipedia) | List of Monorail Systems (Wikipedia) | International Monorail Association

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The icon refers to all regional and mainline systems functioning as rapid transit. It covers S-Trains, Urban Mainline Rail, and Suburban Rapid Transit, including S-Bahn, RER, and all other aliases.

S-Trains are all such systems with metro-like frequency and station spacing in the downtown core or city areas but are primarily focused on the suburbs, with lower frequency branches to serve areas farther from the core. In rare cases such as in Berlin and Copenhagen, S-Train systems may be fully grade separated and/or mode separated, but typically run on/alongside mainline tracks or former mainline tracks.

We use Urban Mainline Rail as a catch-all term for frequent urban rail services that provide radial links around the city center, make local stops on tracks potentially shared with other services, or behave like a Metro line while belonging to the mainline rail network - those are classified under this label as well as long as they act as rapid transit in terms of service. We reserve the right to classify a line that meets the 15 min daily frequency requirement as Regional Rail if the line is not 'urban' enough.

Both S-Train and Urban Mainline Rail services may share track with other services and modes (e.g. tram-trains, freight, and intercity rail), and may have grade crossings (though these are typically controlled crossings with train priority).

If there are many different service/stopping patterns within the core (e.g. there are so many stopping patterns/services that a rider needs to look at a service map to determine if the next train stops at the next station on the line, as in Nagoya or Barcelona) or timetables are required in the core (e.g. stations are served by fewer than four trains an hour during off-peak), lines are considered Commuter or Regional Rail even if branded as S-Trains, as the key differentiating factor between S-Trains and Commuter Rail on this website is the intention for the system to function as or similar to a Metro Line. Note that systems employing local/express with passing tracks are not penalized if stopping patterns are well-defined, unless service frequency drops below 4 trains per hour. Frequent lines may also be considered Commuter Rail if they lack other metro features (e.g. multiple wide doors per car, level boarding, etc) that impact operating speed and passenger experience.

Finally, we use Suburban Rapid Transit for suburban lines built as rapid transit, but which operate independently of any mainline railway. This restriction excludes suburban extensions of rapid transit lines (e.g. lines in Japan where service switches to a different operator at the municipal boundary) and is primarily meant to provide a category for Chinese suburban metro lines.

Subcategories:

• S-Train - AKA S-Bahn, RER, Passante, etc. Base Definition. Branches may be dual-classified under Commuter Rail if service frequency drops below 2 trains per hour or Regional Rail if service frequency drops below 3 trains per hour (note that this is different from our definition of standalone regional rail), and Tram-Trains may be dual-classified under Tram-Train. Examples: Berlin S-Bahn, Paris RER, Crossrail
• Urban Mainline Rail - Mainline Rail lines with high capacity, frequency, and speed. May share track with mainline railways or S-Trains, and typically focus on frequent service in urban areas - effectively a rapid transit service on mainline track. Examples: JR East Yamanote Line, (most of the) London Overground, Moscow Central Circle
• Suburban Rapid Transit - Rapid Transit grade lines primarily serving suburbs. Typically use Metro signaling and rolling stock. Not usually operated by the national railway. Examples: Hanghai Line, Qingdao Metro Line 13, Guangzhou Metro Line 21, Wenzhou Metro, Tsukuba Express

For more information, refer to the following websites: S-Train (Wikipedia)

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The icon refers to medium capacity partially grade separated services, which are characterized by high frequency and substantial grade and mode separation. All Light Rail technology services that run partially at-grade but with limited stations and limited mixed traffic are covered under this mode. Stadtbahn, rapid tram, tram-train, premetro, and modern tramway systems are included under this label. The key differentiating factor between Light Rail and Tramways on this website is the intention for the system to function as or similar to a Metro - lines operating in mixed traffic for significant parts of their route are considered Trams on this website.

Subcategories:

• Light Rail - Light Rail lines with significant rapid transit grade sections operated as a Metro or S-Train but built without intention of conversion to a full Metro system. Many systems feature partial street running and pedestrian crossings at stations, and have discontinuous Metro-grade infrastructure. Grade separation for the majority of major intersections is a requirement. Stations are typically at the same scale as a Metro station. Examples: Denver Light Rail, San Diego Trolley, Utrecht Sneltram, Manchester Metrolink
• Premetro/Stadtbahn - Light Rail lines with significant rapid transit grade sections often built with the intention of conversion to a full Metro system. Examples: Rhein-Ruhr Stadtbahn, Chaleroi Premetro
• Modern Tram - Tram lines constructed after 1985 (Nantes), often at-grade with dedicated rights own way, running on former railway infrastructure, and other Metro features. Grade separation is minimal, though may be present. High floor lines are categorized under Light Rail. Examples: Houston Light Rail, Nantes Tramway, Guangzhou Haizhu Tram
• Subway-Surface Light Rail - Light Rail lines with a grade separated underground trunk like and multiple branching Light Rail/Tram lines, but built without the intention of conversion to a full Metro. Some lines may be dual-classified under Tram/Streetcar. Examples: MUNI Metro, SEPTA Subway-Surface Trolley Lines
• Tram-Train - Tram lines sharing significant amounts of track with active mainline railways or S-Trains/Urban Mainline Rail, as well as Interurban tram lines that run primarily on railway ROWs but are not frequent enough or lack high quality infrastructure and therefore are not considered standard light rail on this website. Some lines may be dual-classified under S-Train, Regional Rail, or Commuter Rail depending on frequency. Example: Karlsruhe Stadtbahn, Aarhus Letbane

Modern Tram Variants:

• Translohr - Tram lines constructed using Translohr technology. Examples: TEDA Modern Tram, Tranvía Ayacucho

External Definitions

American Public Transportation Association (Source)

For more information, refer to the following websites: Light Rail (Wikipedia) | Stadtbahn (Wikipedia) | Premetro (Wikipedia)

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The icon refers to small-scale People Movers. This mode includes small driverless shuttles as well as Personal and Group Rapid Transit. Airport people movers are explicitly not covered in this website - this includes people movers to airports as well as people movers within airports. Exceptions are only made if the airport people mover serves other locations outside of the airport. In a similar manner, tourist rides and shuttles operating entirely within an 'entity' (e.g. Las Colinas APT, Princess Nourah Bint Abdulrahman University APM) are not covered on this website.

Subcategories:

• People Mover - Base Definition. Examples: Miami Metromover.

People Mover Variants:

• Straddle-Beam Monorail - Monorail lines straddling a single beam. Examples: Las Vegas Monorail, Jacksonville Skyway

External Definitions

American Public Transportation Association (Source)

For more information, refer to the following websites: People Mover (Wikipedia)

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The icon refers to street running rail transit such as Trams, Straßenbahn, and Streetcars. This mode covers all such street running systems that run with significant mixed traffic, frequent stops, and/or complex service routing patterns, including historical variations such as street-level cable cars. See Light Rail for services that operate similar to Metros (grade separation, limited stations, streamlined service patterns).

Subcategories:

• Tram/Streetcar - AKA Streetcar, Straßenbahn, etc. Base Definition. Examples: Wrocław Tram, Hiroshima Electric Railway
• Heritage Tram/Streetcar - AKA Heritage Streetcar, etc. Tourist-oriented Tram providing meaningful public transit. Includes both long-lived systems running heritage vehicles and modern systems catered towards tourists. Must operate all year round. Examples: Tampa TECO Line, Dallas M-Line Trolley

Variants:

• Modern Streetcar - Tramways constructed after 2001 (Portland) in the USA, often running in mixed traffic and with capacity similar to that of a bus. Examples: Atlanta Streetcar, Portland Streetcar
• Cable Car - Cable hauled tramways. Examples: San Francisco Cable Car
• Translohr - Tram lines constructed using Translohr technology but which primarily operate in mixed traffic. Examples: Mestre Tramway, Zhangjiang Tram

External Definitions

American Public Transportation Association (Source)

For more information, refer to the following websites: Tram (Wikipedia)

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The icon refers to Bus Rapid Transit. Bus Rapid Transit covers bus systems that behave similar to rapid transit or light rail, with level boarding, dedicated right of way, enhanced stations, transit signal priority, offboard fare collection, etc. Typically, the BRT label applies to corridors rather than services. What constitutes a city having 'Bus Rapid Transit' is determined by the ITDP. See BRT Standard (ITDP) for sources. A list of ITDP-rated BRT corridors on this website can be found at the BRT List.

On this website, we have three subcategories for lower-grade bus corridors. Lack of full-time (all service hours) exclusive right of way automatically disqualifies a corridor from the base BRT classification unless the ITDP rates the corridor Basic or higher. Buses running in shared highways (including HOV/HOT lanes) or with frequencies of 30 minutes or more during peak hours are not considered BRT in any form and are labeled under 'Rapid Bus'. Note that significant infrastructure and service is required to quality as even Rapid Bus - limited stop bus service serving inaccessible (for wheelchairs) stops comprising of only a pole in the sidewalk is not considered a rapid bus on this website, even if the pole is accompanied with a shelter and real time information (as these latter two should be present for even a local bus stop).

Our three lower-grade bus priority modes on this website are BRT-Lite, Arterial Bus Rapid Transit, and Rapid Bus. We use BRT-Lite specifically when referring to busways where the dedicated right of way and alignment are high quality but the corridor fails to meet the BRT Basics minimums. Note that in literature, other types of bus priority are grouped together with BRT-Lite, but on this website we have a separate category for Arterial Bus Rapid Transit. To be categorized as Arterial BRT instead of Rapid Bus, at least 3 of the following are required (Note: Limited Stops, High Frequency, Branding, and Shelters are mandatory): Dedicated Right of Way (part-time and curbside/BAT allowed. Must be at least 50% of route to count.), All-door boarding (requires multiple doors), Level Boarding (see BRT standard. Note that if stairs are required to board the vehicle, it is not considered level boarding), Intersection Treatment (e.g. Transit Signal Priority; turns across ROW forbidden. See BRT standard). This excludes highway based BRT which is Rapid Bus by default.

Subcategories:

• Bus Rapid Transit - Base Definition. Examples: Lima Metropolitano, Curitiba Rede Integrada de Transporte
• BRT-Lite - BRT-lite line featuring a high quality dedicated right of way and alignment but lacking in off-board fare collection, intersection treatments, and/or level boarding. Also applies to corridors where the dedicated ROW is under 3 km. Note: These systems are not considered BRT on this website but are grouped here since some BRT-Lite lines are detailed on this website. Examples: Montevideo Corredor Garzón, Natal Av. Bernardo Vieira
• Arterial BRT - AKA Arterial Rapid Transit (ART). BRT-lite line featuring most but not all BRT features, often running on an urban arterial and often with either part-time curbside lanes or running in mixed traffic with traffic signal priority. Despite the terminology, high quality BRT often uses arterials and is treated differently. Note: These systems are not considered BRT on this website but are grouped here since some ART lines are detailed on this website. Examples: Minneapolis-St. Paul A Line
• Rapid Bus - Catch-all term for highway based BRT branded routes as well as BRT-lite corridors below Arterial Bus Rapid Transit standards Note: These systems are not considered BRT on this website but are grouped here since some Rapid Bus lines are detailed on this website. Examples: Minneapolis-St. Paul Red Line

External Definitions

USA Federal Transit Administration (Source)

For more information, refer to the following websites: Bus Rapid Transit (Wikipedia)

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The icon refers to Funicular systems. Funicular systems feature high grade differences and come in a number of varieties, though only Funiculars utilized as mass transit are covered here - local funiculars that are not integrated into the public transit network are not covered. Notable examples include the Carmelit in Haifa.

For more information, refer to the following websites: Funicular (Wikipedia)

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The icon refers to Cable Propelled Transit such as Aerial Tramways, and Gondola Lifts. Notable examples include the Medellin Metrocable. Cable Cars catered towards tourists or which do not fulfill a rapid transit purpose are not covered at all in this website (e.g. Emirates Air Line).

Subcategories:

• Aerial Tram - System with a single vehicle per cable shuttling between destinations. Examples: Roosevelt Island Tram
• Gondola Lift - AKA Metrocable, Teleférico, etc. System with continuously moving cables with multiple vehicles. Examples: Medellín Metrocable, La Paz Mi Teleférico

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The icon refers to Commuter Rail and select urban Regional Rail systems. This mode covers all such systems utilized for connecting suburbs and/or nearby cities. Commuter Rail is used for peak focused and infrequent service, while Regional Rail focuses on fast and relatively frequent (takt 30 minute service or better) service. Systems with high frequency that operate as rapid transit in the urban core may be considered S-Trains. Other systems with high frequency may be considered Urban Mainline Rail. Metro grade systems running into the suburbs may be considered Suburban Rapid Transit.

Subcategories:

• Regional Rail - Services with takt 30 minute or better service all day every day. Some lines may be dual classified under S-Train or Tram-Train. Examples: Most urban railway lines in the Netherlands and Switzerland, Rhine-Ruhr S-Bahn
• Commuter Rail - Peak-focused and/or infrequent service. Some lines may be dual classified under S-Train or Tram-Train. Examples: Long Island Rail Road, MBTA Commuter Rail

External Definitions

American Public Transportation Association (Source)

For more information, refer to the following websites: List of Suburban and Commuter Rail Systems (Wikipedia) | Commuter Rail (Wikipedia)

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For further reading on transportation modes:

• S-Bahn and Regionalbahn (Pedestrian Observations)
• What is Light Rail Anyway? (Pedestrian Observations)

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Notes on Mode Classifications:

When this site was first conceived, we had an explosion of modes. Automated Guideway Transit and VAL had separate icons from Light Metro, RER was separate from S-Train, etc. However, which mass transit solution is chosen depends on the city's needs, and the vast amount of hybrid systems added many complications.

Some icons were retired since they were just another icon in a different language. Other icons were retired since they were subcategories of another. And some icons were retired because it was simply impossible to formally declare a cutoff between them and another mode, as was the case with Light Metro.

The are many different types of urban mass transit, especially in rail transit. There are systems that run as metro lines but with low floor light rail vehicles (Ottawa Confederation Line, Sevilla Metro). There are high floor metro lines with grade crossings (Chicago, Rotterdam, Oslo). There are strange oddities such as the Norristown High Speed Line in Philadelphia. There are tram lines that run underground in city centers (Premetro/Stadtbahn/Subway-Surface), and there are tram lines that run on dedicated rights of way outside of city centers (Tram-Train).

And none of this even discusses branding. Light Rail and Light Metro can be grouped together or separately depending on the jurisdiction. People Movers and Light Metro can be grouped together. Some urban services on mainline tracks are referred to as Rapid Transit (Bilbao, Naples, Barcelona). Some S-Trains are basically just rapid transit lines (Berlin, Copenhagen). Other S-Trains are regional lines diverted into a rapid transit corridor (Japan, Paris RER A, Crossrail Elizabeth Line). Yet other S-Trains are just commuter rail lines with a tiny connector to allow for through traffic (Paris RER C). And yet other S-Trains are branded as Rapid Transit despite requiring timetables (Valencia).

All of these exceptions led to a massive simplification in the major mode groupings used on this website. The truth is that each city has its own needs, and attempting to classify with hard lines is incredibly difficult. We will continue to perform classifications, but in the end, what is most important is providing maps that are useful to the people who use them.