Google Transit Feeds and Mass Transit Mashups

Mass transit in metropolitan regions is becoming an increasingly popular mode of transportation for commuters faced with ever-increasing oil prices. As a result, there is an emerging need for mass transit agencies to make information more accessible to a growing number of commuters. What role can APIs play?

Google's Transit Feed Specification

Although widespread mass transit APIs may not be readily available, Google's Transit Feed Specification (GTFS) holds some promise for agencies seeking to integrate their data with Google's Transit Planner as well as the public and would-be transit mashup developers.


The rationale behind the GTFS is that it enables agencies to provide public transportation schedules to Google for incorporation into Google Maps and other Google applications. The GTFS provides an opportunity for transit agencies to share route data that can be distributed easily to a wide consumer base via Google's applications, while at the same time allowing that data to be shared with the public in a standardized format. The end result: transit agencies can better serve their customers through improved and expanded information sharing.

Mass Transit Agencies

Based on an effort initially led by Portland, Oregon's TriMet, data in GTFS format from several transit agencies has been successfully incorporated into Google's Transit Planner, including BART in the Bay Area, TBC in Bordeaux, France, and Transperth in Perth, Australia.

Google Transit

You can browse the list of agencies that are participating in Google Transit to get an idea of which agencies currently publish their data using the GTFS. The list has been growing incrementally since Google Transit's initial debut in 2006, and effort's such as this year's "Google Transit's Earth Day Challenge" have helped to garner increasing participation from transit agencies.

There is also a list that shows which agencies have publicly accessible data feeds. We hope to see this list grow in the near future.


There are several efforts underway to leverage transit for use in application and mashups. Open source projects, such as the GoogleTransitDataFeed project and the Transit TimeTable Publishing Application, seek to provide a common set of tools for agencies to distribute data in GTFS format. And creative developers have tapped into transit data to create valuable tools and mashups.

Transit mashups are primarily map based, including such sites as the Montreal Transit Planner, Chicago Transit CTA and Metra Rail, and Transit Maps, a slick map mashup that allows users to interactively view transit routes on Google Maps.

Matt King has developed Trimet Tracker, an iPhone application that allows users to search for transit arrival times and transit routes (it uses an API provided by TriMet). Other applications, such as TrainCheck provide train arrival times via SMS or email to user's mobile devices (currently only available for San Francisco, Washington, D.C., and Caltrain).

iPhone Trimet

As transit agencies move forward with increased data sharing efforts, particularly with GTFS, we hope to see a proliferation of transit mashups and applications (home-grown, open source, or commercial) that assist metropolitan commuters.

The Public

Ultimately the public is the key beneficiary of mass transit data Integration via the GTFS format. In addition to utilizing Google Transit, commuters have gained access to various types of applications that deliver transit routes and schedules in innovative ways. We hope to see additional transit agencies joining in this data sharing effort, and we look forward to seeing how innovative developers will integrate publicly shared transit data.

For more, check out over 80 transit mashups in our mashup directory. We also have several travel APIs listed in our API directory, including the HopStop API, which provides subway and bus directions for New York City.

Be sure to read the next Mapping article: Yahoo Local API Now Lets You Search Along Routes