Denver Transit Lines 1600 Blake St The Regional Transportation District (RTD) provides Colorado with quick, safe, and reliable public transportation in the Denver metro area, including Boulder. Trip planning, schedules, maps, fares, and transit news. FasTracks is RTD�s voter-approved transit program to expand rail and bus service throughout the Denver metro area. Denver CO Transit Lines RTD Regional Transportation www.rtd-denver.com RTD RTD Denver Regional Transportation District Denver transportation Denver mass transit Boulder transportation Colorado transportation Colorado transit Denver transit transportation to DIA transportation to Denver International Airport RTD RTD Denver Regional Transportation District Denver transportation Denver mass transit Boulder transportation Colorado transportation Colorado transit Denver transit transportation to DIA transportation to Denver International Airport Business Reviews RTD Regional Transportation Testimonials