Area Closure and Condition Updates
OSMP makes every attempt to keep this page as up to date as possible. However, some closures and trail advisories are made on an emergency basis for the safety and well-being of our visitors, wildlife and natural resources. Please watch for these signs during your visit.
The types of closures and the dates they are typically closed are listed below, click each for more information:
Trail closures, advisories and fire bans:
Boulder Falls Trail to remain closed
Boulder Falls Trail will remain closed for some time. While OSMP hoped to be able to open the trail on May 1 as usual, due to the unusual number of snow storms and amount of snow received in April this year, the scaling that needs to be done before opening the trail was not possible. This work will be completed as soon as it can be arranged so the trail can be opened.
Sanitas Valley Trail temporarily leash-required because of coyote activity
Dogs must be on a handheld leash on the entire Sanitas Valley Trail because of coyote activity in the area. OSMP will monitor the situation and inform the public when it is once again safe to walk dogs under voice and sight control.
Third Elephant Buttress temporarily closed April 20, 2013
The main climb Standard Route of the Third Elephant Buttress is temporarily closed because of a large, unstable rock that needs to be removed. This notice will be removed when the area is open again. 
Closure notice421.58 KB.
Flagstaff Fire Closures - updated November 13, 2012
Now open: Bear Peak West Ridge is open. Fern Canyon is open to the summit of Bear Peak. Visitors must remain on trail.
Still closed:
- Due to significant erosion as a result of the Flagstaff Fire, much of the Shadow Canyon Trail remains closed. The closure begins approximately 0.4 mile west of the junction with Shadow Canyon North, which allows visitors to access The Maiden climbing area. OSMP staff are evaluating Shadow Canyon Trail in preparation of rehabilitation work that is planned to begin as early as spring 2013, with the hope of opening the trail by early summer 2013.
- South Boulder Peak and the upper portion of Shadow Canyon remain closed.
- View Fire Closure Map
August 7, 2012 Flagstaff Fire Update
- On June 26, 2012 a lighting strike ignited a wildland fire on OSMP land on the west side of Bear Peak. A combination of incredible initial aerial attack, favorable weather conditions and the hard work of fire fighting hand crews contained the fire on July 5.
- OSMP in cooperation with the wildland fire management staff closed the area around the burn for reasons of public safety and resource protection.
- On July 24, 2012 OSMP rolled back the closure area to allow access part way up Fern and Shadow Canyon trails providing access to some of the popular climbing features in this area.
- On August 14, 2012 OSMP opened the Fern Canyon trail to the summit of Bear Peak.
- On November 13, 2012 OSMP opened Bear Peak West Ridge trail.
- OSMP will continue to assess and monitor this area to determine when it is sufficiently safe and sustainable to allow for visitor access.
- Please continue to watch this site for changes and updates about trail access into the burn and surrounding area.
- View a photo gallery of the burn area.
Mallory and Harmon Caves closed year-round, effective Sept. 21, 2010
Concerns about a national epidemic of white-nosed syndrome, which has led to massive die-offs among bats has led OSMP to close Mallory and Harmon Caves year-round to protect Townsend's Big-eared bats. White-nosed syndrome is a fungal disease that has decimated bat populations in the East. The U.S. Forest Service closed all caves on National Grassland and Forest properties across several states, including Colorado, in an attempt to limit the potential for spread in the Western region. The spread of the disease, largely in recreational caves, suggests that people may be one of the most significant methods of spread between caves. This closure will remain in effect until the threat to the ecosystem has been mitigated. Map of bat closure areas
Dry Creek closure due to non-native New Zealand mudsnails, effective Sept. 21, 2010
Non-native New Zealand mudsnails have been discovered on OSMP property; Dry Creek is closed to prevent the mudsnails from spreading. Dry Creek Trail and Trailhead are open. Dogs must stay out of Dry Creek; dogs may access water where the trail crosses the ditch. This closure will remain in effect until the threat to the ecosystem has been mitigated. For more information, please visit the New Zealand mudsnails closure page.
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.
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Seasonal leash restrictions
Dogs must be on leash from Aug. 15 through Nov. 1 on the following trails because of bear activity:
These areas are frequent foraging locations for bears. Leash restrictions protect dogs and their guardians when there is a high probability of encountering bears, and help avoid disturbing bears while they feed during this critical pre-hibernation period.
Lower Big Bluestem Trail is leash-required year round.
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Seasonal Grassland ground nesting bird closures in effect May 1 through July 31
Grassland breeding birds have seen widespread and precipitous declines at a continental scale due to a variety of impacts. OSMP provides habitat for several species of grassland nesting birds including Grasshopper Sparrow, Western Meadowlark, Vesper Sparrow, Horned Lark, Lark Sparrow, and Savannah Sparrow.
These closures do not affect designated trails in the area which remain open throughout the closure period.
The following areas are closed May 1 - July 31:
- Both sides of the Greenbelt Plateau trail from the Community Ditch trail to the Greenbelt Plateau trailhead on Highway 128. Dogs must be on-leash on the Greenbelt Plateau trail;
- the area north of Community Ditch trail and west of Highway 93;
- the area north of Flatirons Vista North trail and west of Highway 93 on top of the mesa; and
- the area north of the South Boulder Creek West Trail, east of the Bluestem Connector and sotuh of Shanahan Ridge (dogs are prohibited off-trail in this area year round). Dogs must be on-leash on Lower Big Bluestem.
Closure Maps:
Greenbelt Plateau / Doudy Draw Area 590.2 KB
Lower Big Bluestem Area 630.37 KB.
Grasshopper sparrow nestlings
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Bat roosting site closures
Female bats locate roosting sites in caves and rock crevices along the foothills, where the pups are raised in maternity colonies. The pups suffer high mortality rates even under normal conditions, so these seasonal closures help ensure they will remain undisturbed by humans during roosting season. Thank you for your cooperation!
Map of bat closure areas694.11 KB
Seasonal closures:
- The east face of the climbing formation known as Der Zerkle is closed April 1 - Sept. 1 every year (picture below).
- A buffer surrounding Mallory Cave will be closed April 1 - Oct. 1 to protect Townsend’s Big-eared Bats. Instead of being part of the permanent Mallory Cave closure, the climbing routes on the east face of The Hand, the standard route on the Finger Flatiron, and all of Shark’s Fin will now be opened on Oct.1.
Permanent closures:
The following areas are closed permanently to human use to reduce the chance of humans introducing White-Nose Syndrome.
- Mallory Cave (picture below)
- Harmon Cave (picture below)
- Seal View Cave
Der Zerkle East Face - closed April 1 - Sept. 1 every year
Mallory Cave - closed year-round over white-nose syndrome concerns.
Harmon Cave - closed year-round over white-nose syndrome concerns.
Seasonal Raptor closures:
Please help us protect wildlife by:
Respecting all area closures.
Immediately leaving any closure area should you accidentally enter one.
Urging cooperative respect for closures from fellow park users.
Municipal fines are up to $1,000 and jail time up to 90 days.
Follow this link to meet some of the animals protected by these closures.
Bald Eagle nesting closures run from Nov. 1 until July 31.
Cliff Nesting Raptors are protected from Feb. 1 through July 31.
Burrowing Owls are protected March 15 through Oct. 31.
Osprey are protected March 15 through Sept. 10.
Bald Eagles:
Kolb and Coal Creek Property Closure: The Kolb property in the White Rocks area (near 75th and Valmont) and the Coal Creek Property (east of Hwy 93 and near Marshall Lake) are closed temporarily between Nov. 1 and July 31 to protect bald eagle nesting and roosting activity.
Coal Creek 2.64 MB
Kolb Property Closure 606.73 KB
Cliff Nesting Raptors:
Thanks to OSMP visitors and volunteers for supporting these closures and the cliff-nesting raptor program!
Overview Map of OSMP: This map shows all of the cliff nesting raptor closures from Feb. 1 - July 31.
The following areas are closed every year from Feb. 1 - July 31 to protect cliff nesting raptors:
Mickey Mouse Wall - Mickey Mouse Wall and all terrain within 100 yards of the wall closed, this includes South Tower, North Tower, Central Tower, Ship's Prow, Wall of Shiva's Dance, The Gargoyle, the East Face and Cryptic Crags.
Back Porch, The Box - The Back Porch and The Box are closed.
Bear Creek Spire - Bear Creek Spire is closed.
Flagstaff North - A portion of the northside of Flagstaff Mountain is closed.
The entire Third Flatiron - Including Queen Anne's Head, W.C. Fields Pinnacle, 1911 Gully and the Ghetto, the East Bench & West Bench, the East & West Ironing Boards, The Fin, Green Thumb, and Jaws are closed. Royal Arch Trail is open.
Skunk Canyon - The Skunk Canyon drainage west of the Mesa Trail, starting at and including the Second Ridge is closed, including Ridge Two, Ridge Three, Ridge Four, the Achean Pronouncement, the Dreadnaught, and the South Ridge of Green Mountain known as the Sacred Cliffs.
North side of Fern Canyon - The area north of the Fern Canyon Trail, including the Nebel Horn Ridge, East Ridge, the Goose and the Goose Eggs is closed. Fern Canyon Trail is open.
The Sphinx - The Sphinx is closed.
Shadow Canyon - Including Devil's Thumb Ridge, Towers of the Moon, and Jamcrack Spire are closed. The Maiden is open with access from the east side only. Diamond Head and The Matron are now open. The upper part of the Shadow Canyon Trail is closed from the Flagstaff Fire, please review the fire closure map.
Closure lifted 5/15/13 - Mt. Sanitas Ridge - The Sanitas closure has been lifted for 2013.
Closure lifted 5/14/13 - Lefthand Canyon Palisades - The Lefthand Palisades closure has been lifted for 2013.
Closure lifted 5/8/13 - Gregory Canyon Amphitheater The Amphitheater closure has been lifted for 2013.
Burrowing Owls:
These areas are closed to protect nesting burrowing owls every year from March 15 - Oct. 31:
Superior Associates
Mesa Sand and Gravel
Kelsall
Map depicting Superior Associates, Mesa Sand and Gravel, and Kelsall Burrowing Owl Closures
Cosslett/Knaus Burrowing Owl Closure
Jafay/Lynch Burrowing Owl Closure
Damyonovich/Yunker Burrowing Owl Closure
Osprey:
The Axelson area near the Boulder Reservoir is closed to protect nesting Osprey every year from March 15 - Sept. 10:
Axelson Osprey
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New Zealand Mudsnails:
Dry Creek Closure to all access for New Zealand Mudsnails
Boulder Creek closure to all access for New Zealand Mudsnails
Last Updated on Monday, 20 May 2013 08:09
Open Space & Mtn Parks 