Public transit in Denver is operated by the Regional Transportation District. RTD is the transit system for the Denver metro area. RTD provides service over a 2,400 square mile area and the services include buses, light rail, and a bus to Denver International Airport. RTD boasts 140 local, express, regional bus routes in addition to their five light rail routes. It is not inexpensive, however, to take advantage of their services.
RTD provides PDF system map inlays for the smaller areas.