Documentation
The General Transit Feed Specification is documented on a Google Code site.
Tables in our feed
We currently include the following tables in the CTA GTFS Feed (links point to more detailed information on Google Code):
- agency.txt - basic agency information
- stops.txt - list of stop locations for bus and train, also includes parent station info for trains
- routes.txt - route list with unique identifiers
- trips.txt - has information about each trip taken by a CTA vehicle
- stop_times.txt - scheduled arrival/departure times for each stop on each trip
- calendar.txt - defines which service IDs operate on which days
- calendar_dates.txt - has exceptions to calendar (such as a holiday when a Sunday schedule is operated)
- shapes.txt - defines how to draw a route line on a map
- frequencies.txt - defines headways when trips aren't specifically scheduled, but sent as-needed (such as service that follows a major event)
- transfers.txt - has additional information to guide trip planners into identifying two stops as a transfer point and how much extra time to give people to transfer between services