Rapid Transit Database

Rapid transit is public transportation that is separated from other traffic. It may use buses or railways, but those vehicles must operate on dedicated, separated infrastructure. Rapid transit is the backbone of a city’s public transportation system because it allows people to travel quickly between different neighborhoods.

For a corridor to qualify as ‘rapid transit’ in the RTDB, it must meet the following criteria:

Bus Rapid Transit (BRT) and Light Rail Transit (LRT) must meet the “BRT Basics” definition in The BRT Standard:

• A section of road, or contiguous roads, at least 3 kilometers (1.9 miles)
• Dedicated lanes for transit vehicles
• One or multiple routes

BRT and LRT corridors must have five essential elements:

• Dedicated right-of-way: The corridor must be segregated from other vehicle traffic by physical separation, color-differentiation, or other clear delineation.
• Busway alignment: The corridor must be located to limit where conflicts with other vehicle traffic. Center-aligned or BRT/LRT–only corridors are preferred.
• Off-board fare collection: Fares are collected off-board. This includes the use of barriers like gates or turnstiles or proof-of-payment (fare purchased off-board and checked on-board) systems. On-board fare validation at all doors is acceptable but reduces efficiency.
• Intersection treatments: Other vehicles are prohibited from turning across the busway, or BRT/LRT vehicles must be given signal priority at intersections to help to reduce travel delays.
• Platform-level boarding: The floor of BRT/LRT vehicles must minimize vertical and horizontal gaps so that the station platform and the boarding vehicle are level and barrier-free for those with movement disabilities.

Metro is defined as any rail-based transit mode that features:

• Grade separation: Service must be completely grade separated from other private and public transportation.
• Off-board fare collection: Fares are collected off-board. This includes the use of barriers like gates or turnstiles, or proof-of-payment (fare purchased off-board and checked on-board) systems. On-board fare validation at all doors is acceptable but reduces efficiency.
• Regular station spacing: Service operates entirely within a single built-up urban area with regular station spacing (<5 km between stations, excluding geographic barriers to development, such as mountains and bodies of water).
• Frequent service: Service operates at headways of less than 20 minutes in both directions, from at least 6 am to 10 pm.
• Capacity-oriented: Railcars prioritize capacity over seating provision.

The RTDB might exclude corridors, even within the same system, that seem like rapid transit but do not meet the above essential characteristics.

The RTDB uses population estimates for urban areas from the United Nation’s 2018 Revision of World Urbanization Prospects. These reflect urban agglomerations, rather than municipalities as they may be legally understood.

The Rapid Transit to Resident Ratio (RTR) is a small statistic with a lot of information. The metric compares the length of rapid transit lines (including rail, metro, and BRT) with a city or country’s urban population (cities with over 500,000 people). This metric offers a snapshot of how transit infrastructure compares to population. Because RTR considers the population of a city or country, it shows a more meaningful picture of transit quality than a simple measurement of transit length.

RTR is a useful metric, but it must be considered critically and in context, especially at the city level. Some cities with high RTR numbers do not have transit systems that serve all residents equitably and effectively. For example, a city may have a high RTR, but if the rapid transit corridors are relegated only to wealthy enclaves, low-density districts, or fail to travel to important destinations like job centers, then the high RTR number can conceal the poor quality of actual service. RTR should always be supplemented with an understanding of the geographical relationship between transit and population within a city.