Important Updates:

The city expands beta to preview its new website and gather feedback. | More Info


The City of Boulder welcomes your feedback. Use our Inquire Boulder customer service tool to tell us what’s on your mind.

  • OSMP Trails & Recreation
  • OSMP Visitor Info
  • OSMP Get Involved
  • OSMP Nature & Restoration
  • OSMP - About
  • OSMP Kids & Families
  • OSMP Plans & Reports
  • OSMP en Español

Temporary Closures, Advisories and Fire Bans

Trail Map

Open Space and Mountain Parks (OSMP's) interactive trail map includes trail closures - an easy option to check before your trip!

OSMP Alerts


People enjoy open space for physical, emotional and mental health. Remember to always be courteous. Don't forget to: 

  • Plan visits ahead of time and don’t park illegally at full trailhead areas.
  • Remember to “keep the space in open space.” Maintain 6 feet of distance from people not in your household.
  • Leave No Trace. Stay on trail and walk through mud. If you step off trail to let others pass, immediately step back on trail. 
  • Protect first responders. Know your limits and don’t take unnecessary risks.
  • Visit to see current trail closures, historical data that shows areas of high and low open space use and trails that are wider than 6 feet. See when trails are busiest through our Visitation Data Explorer.

Muddy Trail Closures

Text “OSMP” to 888-777 to sign up for text updates about muddy trail closures.

OSMP Closed Trails
Muddy trail closures as of Monday June 14, 2021.

No trails are currently closed due to muddy conditions.


Other Trail Closures and Advisories

Doudy Draw Trailhead closed on June 16, 2021
The trailhead parking lot will be closed to vehicles on Wed. June 16 from 6 am to 4:30 pm for maintenance work. Nearby trails will remain open to the public; please use caution accessing them through the trailhead as heavy equipment will be in use by OSMP staff.

IBM Connector Trail underpass flooding
Visitors may encounter flooding in the IBM Connector Trail underpass during springtime and after heavy precipitation. The city is working to determine the cause of the flooding.

1st/2nd Flatiron Trail closure beginning June 7, 2021
The 1st/2nd Flatiron Trail will be closed from 8 am - 4:30 pm, Monday through Thursday, every week, beginning Monday, June 7 and ending in early-September. The closure will start at the base of the 1st Flatiron. Climbers may climb the 1st and hike down the trail, but may encounter significant delays. OSMP will continue needed repair efforts, including rebuilding stone structures along the trail and restoration; trail closures are necessary for visitor safety. 

Bear Canyon Trail closure beginning May 24, 2021
The Bear Canyon Trail, west of Mesa Trail, will be closed from 6 am to 5 pm Monday through Saturday beginning May 24. Intermittent Saturday closures along the path are anticipated to occur in the coming months. More information about this trail closure can be found on

Royal Arch Trail closed through fall 2021
The Royal Arch Trail is closed 24 hours a day through fall 2021 while OSMP conducts extensive maintenance, including the building of several large stone structures. OSMP understands the impact this extended trail closure will have on open space visitors, but it is necessary to help complete trail maintenance as quickly as possible.

Cottontail Trail closure starting June 17, 2021
OSMP is beginning work on two sections of the Cottontail Trail – a part of the Longmont-to-Boulder Regional (LOBO) Trail northeast of Boulder – to conduct trail resurfacing and other maintenance work. Starting June 17, OSMP will temporarily close the 0.5 mile section of Cottontail Trail south of State Highway 52 to the Boulder White Rock Ditch from 8 am to 4:30 pm Monday-Friday for 8 weeks, depending on weather. Additionally, the section of Cottontail Trail that heads directly south of the Boulder White Rock Ditch to Lookout Road will be closed 24 hours a day, 7 days a week until late-fall, beginning July 1. When this closure is in effect, cyclists can reconnect with the LOBO Trail by using:

  • State Highway 52 to 71st Street to Lookout Road
  • North 79th Street to Lookout Road.

View the trail closure sign pdf for a map showing these closures and detour options. 

South Boulder Creek access closure between South Boulder Road and Marshall Road beginning Oct. 29, 2020
Access to South Boulder Creek between South Boulder Road and Marshall Road is temporarily closed to help prevent the spread of invasive New Zealand mudsnails (NZMS). Please visit NZMS page for details. The South Boulder Creek Trail remains open.

Boulder Star area closure
Oct. 20, 2020: OSMP will continue the existing closure around the Boulder Star area on Flagstaff Mountain and will replace temporary fencing with reinforced wood fencing in the area. Learn more about the Boulder Star closure.

Anemone Hill Trail Construction beginning May 14, 2020
Please visit for details on this project and trail closures.

Gregory Canyon restroom closed 
The restroom is temporarily closed because of maintenance issues. This notice will be removed when the restroom has been reopened.

Chapman Drive and Boulder Falls impacted by work in Boulder Canyon
Visitor access to these areas – either by bike, by car or by foot – will be limited while the Colorado Department of Transportation conducts work in Boulder Canyon. For specific closure times, please visit the project website. Boulder Falls is currently open. Temporary closures will still occur until construction is complete. 

Rock Island 1 in Boulder Canyon closed
Rock Island 1 is closed. The rock fractured and part fell onto the Boulder Canyon Creek path. Sections of the remaining rock have been evaluated as unstable so it is closed until recommended bolting can be completed.   

No parking along Highway 170 near Doudy Draw and South Mesa Trailheads
Please remember that parking is not allowed on Highway 170 at any time.