4 Apr 2023 by David Mountain

Bus route geometry is a fundamental building block for public transport  information. Bus schedules tell you which buses will depart what stop,  when, and bus stops often have a point latitude and longitude associated  with them. But without the street-level geometry between stops, bus  routes are jagged, cut across the road network, and do not show where  the buses actually go.

The most obvious use for bus route geometry is to show the route over a map. Either as an overview of the entire service, or as a backdrop for the live bus locations. The bus route geometry is also used in more subtle ways in the background. It is essential for tracking a buses progress through its scheduled journey, and accurately calculating not only which bus stops it is between, but its progress between them. This allows “ladder” views of bus journeys that accurately portray how far between stops a bus is, and is also crucial for prediction engines to calculate estimated arrival and departure times.

TransportAPI have developed an approach to calculating bus route geometry that has led to the most complete and accurate set of bus network edges for mainland GB bus services. Their approach is to cascade through the most reliable source of geometry for each service. The most trusted source is direct from operators, and TransportAPI have an arrangement to download direct from several of the main bus operators. Where this is not available, TransportAPI use geometry from the Bus Open Data Service (BODS) where many operators choose to include geometry as part of the upload of their bus schedules. However, many operators either choose not to include this, or are unable to, since it has never been created! In these cases, TransportAPI have developed a bus profile for a road-based journey planner, that accounts for the constraints and permissions that buses have on the network, and calculates the route over the street network that the bus is most likely to take.

Our clients are also surprising us in the ways in which they are using these endpoints. A current use case is identifying bus services that will be affected by future roadworks, bus operators can be made aware and alter the route and schedules, if required.

This geometry can be accessed in different ways. See the Usage Examples covering how to show geometry for a bus journey or one or more bus services.

Get in touch if you’d like to find out more about our TAPI’s Bus Information Managed Service.