Open Space and Mountain Parks

Boulder's Open Space and Mountain Parks (OSMP) are a very special place. The open space lands teem with native plants and wildlife and are home to threatened and endangered species. They serve as a buffer between Boulder and nearby development. They sustain agriculture uses and add untold benefits to the natural environment - clean air, water, and earth.

The lands shape the urban mosaic of the Boulder Valley and provide residents with passive recreation opportunities. Trails are used by walkers, hikers, bicyclists, horseback riders, dog walkers and other passive recreational uses.

OSMP Alerts

Trail/Trailhead Closures

Please see the temporary closures page for more details on the trail closures below. OSMP's interactive trail map also shows these longer-term trail closures and restrictions:

Muddy trail closures: Please check the trail map or temporary closures page for any muddy trail closures.
Xcel Energy electric transmission line work: Xcel anticipates starting work in the NCAR area as early as the week of July 22.
Fourmile Canyon Creek Trailhead closure: The trailhead will be closed on Thurs. July 25 for maintenance.
Boulder Falls closure: Boulder Falls Trail is closed to complete additional trail-related repairs in the area.
1st/2nd Flatiron Trail closure: The 1st/2nd Flatiron Trail will be closed Mon-Thurs every week into the fall.

Project Updates & Other Alerts

OSMP Master Plan Update: Read the Final Draft of the OSMP Master Plan . Thank you to everyone who shared your input!

Tall Oatgrass Management Program: Learn about why it's so important to aggressively manage tall oatgrass in Boulder County and what OSMP is doing about it:

OSMP administrative offices have moved: The offices relocated to 2520 55th St. in Boulder.

Purchase OSMP annual parking permits online: Visitors whose vehicles are registered outside of Boulder County can now purchase OSMP annual parking permits online. Learn more about parking permits.