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Boulder Valley Ranch Trailhead

Boulder Valley Ranch Trailhead

Eldorado Canyon to Walker Ranch Connection Feasibility Study findings and recommendation meeting

The findings of a feasibility study and a preliminary recommendation for a preferred trail alignment between Walker Ranch Open Space and Eldorado Canyon State Park will be presented from 5:30 to 7:30 p.m., Nov. 28. This meeting will be held at City of Boulder Open Space and Mountain Parks 2520 55th Street, Boulder. Learn more.


One mile north of Boulder on Highway 36, then one mile east of Highway 36 on Longhorn Road (a dirt road). The turn-off from the highway onto Longhorn Road is marked with a sign for Boulder Valley Ranch Open Space.     

Please check for Trail & Area Closures.

Or view the interactive trail map (includes trail closures) and the interactive wildlife closures map

You are responsible for knowing and complying with all closures and OSMP rules & regulations.

Open Space and Mountain Parks Master Plan

Open Space and Mountain Parks (OSMP) has kicked off a long-term effort to establish a community-supported plan that will guide the management of the community’s open space over the next decade and beyond. Learn more about the OSMP Master Plan.

Pilot Cobalt and Eagle Trail Use Designation Changes

OSMP is seeking input to determine whether it needs to re-designate the Eagle and Cobalt trails. Recently, visitors expressed concern about the possibility of injuries on the Eagle Trail because a short section of it is significantly steeper and more technical than all other trails in the Boulder Valley Ranch area. Learn more and share your feedback. 


Parking lot on south side of Longhorn Road.


Please keep your car doors locked and your car windows rolled up at all times while leaving your vehicle parked at OSMP trailheads. Also consider leaving important valuables at home or take them with you while visiting open space. To report suspicious activity please call City of Boulder Dispatch 303-441-3333 or Boulder County Dispatch 303-441-4444. For crimes in progress, call 911 immediately.


View Boulder Valley Ranch Trail Map pdf

The Eagle (2.6 mile from Mesa Reservoir to Eagle Trailhead) and Sage Trails (1.8 mile ) form a loop between this trailhead and the Eagle Trailhead. Heading southward on the Sage Trail you can either take this loop or head westward on the Cobalt Trail below an old smelter of 1930s to 1940s vintage and connect to the Eagle Trail as it heads toward the Foothills Trailhead. Another option is to pass the Cobalt Trail (0.9 mile) and take the Eagle Trail as it turns up toward the Mesa Reservoir (the reservoir is sometimes dry). A loop hike is available in the Mesa Reservoir area by following the Hidden Valley (1.0 mile) and Mesa Reservoir Trails (0.8 mile).


This area is identified as being popular with people using wheelchairs. See the Accessible Trails Page for details.


Located at the trailhead.


No picnic facilities.


Bicycles are allowed on the Eagle and Sage Trails. Bicycles may be ridden only on those trails that are posted with the international bicycle symbol. Other bike trails on OSMP.


Boulder Valley Ranch Area Dog Regulations Map

Learn about bringing your dog to OSMP. All dogs must be leashed in the Trailhead Leash Area. Beyond the trailhead, dog control requirements vary from trail to trail, so carefully watch for dog regulation signs at trailheads and trail intersections. On most OSMP trails in this area, dogs must be on a hand-held leash at all times unless they meet the voice and sight control standard and display a City of Boulder Voice and Sight tag. Dog excrement removal is required by law.


Allowed on most trails. Off-trail riding is discouraged to protect rare plants and wildlife habitat. Learn more about riding your horse on OSMP.


There is an abundance of raptors: eagles, northern harriers, red-tailed hawks may be observed. Mule deer and coyotes are frequently sighted. Many snakes can be found in this area including rattlesnakes and bull snakes.

Boulder Valley Ranch is home to a fragile plant community on the black "Shale Barren" soils. Bell's Twinpod is a very rare plant that is unique to shale soils of Front Range Colorado.


  • Present working and historic ranch.
  • Remnants of a smelter on the south side of Longhorn Road.
  • The 1990 Olde Stage fire burned in this area.
  • Silverlake Ditch fed Mesa Reservoir until abandoned. Mesa Reservoir is now dry.
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