To Denver   

The Flatiron Flyer (FF) is RTD’s Bus Rapid Transit service along Highway 36.  It includes six route options.  For specific routes, schedules and details, visit the Flatiron Flyer webpage

Flatiron Flyer Routes

  • FF1 – Downtown Boulder to Denver’s Union Station (all 6 BRT stops)  
  • FF2 – Express to Denver with stop at McCaslin (CU Denver) 
  • FF3 – Broomfield to Denver 
  • FF4 – Boulder Junction to Denver Civic Center Station 
  • FF5 – Downtown Boulder to Anschutz Medical Center 
  • FF6 – Denver Union Station to Boulder Junction (East Campus) 

To the Airport (DIA) – SkyRide 

With one stop adjacent to CU Boulder at 16th and Broadway, the SkyRide leaves hourly from Boulder Station, 18 times a day.  Free with an EcoPass or College Pass. Visit RTD’s SkyRide website for more details.  

To Longmont & Fort Collins

If you are commuting to Longmont or further north, the following bus services provide the best options.  Visit the City of Boulder bus website or use RTD’s Trip Planner to plan your commute.

Bus Routes North

  • BOLT - Longmont via 28th then Diagonal Hwy
  • J (Route) - Longmont via Foothills Parkway, Jay Rd, Gunbarrel, Diagonal Hwy 
  • FLEX - Fort Collins - Loveland - Longmont - Boulder

FLEX service is provided by TransFort out of Fort Collins.  RTD EcoPasses are accepted on FLEX.  For details and schedule, visit the Transfort website.   

For other options between Boulder and Longmont, see the Boulder County Transit Map 

To Golden 

  • GS (Route) - Downtown Boulder to Golden via Broadway and Highway 93 

To the Mountains/Slopes