Page Type: Mountain/Rock
Lat/Lon: 38.86130°N / 105.637°W
County: Park
Activities: Hiking
Season: Spring, Summer, Fall, Winter
Elevation: 10020 ft / 3054 m


At the summit of Threemile MtnAt the summit of Threemile Mountain

Threemile Mountain juts out of the high prairie of southern Park County. It sits relatively isolated, and provides fine views in most directions from its rocky summit. This is a cool little peak with a rocky finish, and even in the dead of winter demands a relatively small price in terms of overall level of effort to reach its 10,000+ foot summit and enjoy the breeze and the views.

Like neighboring peaks in this area, Threemile Mountain rises out of a dry, grassy plain and has sparse, scrubby trees on its upper slopes and near its summit. The summit area is craggy enough to deter tree growth and provide fine views, even of the distant Sawatch.

Rank: 2,296th highest peak in Colorado
Prominence: 560 feet
USGS Quad: Dicks Peak

Rank and Prominence Source: Lists of John

Getting There

Threemile Mountain_Getting There

Threemile Mountain is east of CO Hwy 9, roughly 15 miles south of the town of Hartsel on US Hwy 24. The peak is in far southern Park County near Thirtynine Mile Mountain, about 8 miles as the crow flies southwest of Eleven Mile Reservoir.

Red Tape

Northward from the summit areaNorthward from the summit area
Sawatch Range from the summitSawatch Range from the summit

Very few rules govern your use of this part of the National Forest. There are privately-held ranches nearby, however; be mindful of avoiding private property. There is no fee to use this part of the National Forest and parking is free.


Scrubby trees below the summitScrubby trees below the summit
UN 9900 from ThreemileUN 9900 from Threemile

Immediately Surrounding the Peak
This peak is close to roadways and clean, reliable water sources are scarce. Camping right near the peak cannot be recommended.

US Forest Service Campgrounds

The National Forest Service has a large selection of campgrounds in and around the Lake George area.

Campground NameElevationSitesNightly RateReservations?Notes
Blue Mountain8,200 ft.21$12YesLess than 3 miles as the crow flies from the summit of Blue Mountain.
Spruce Grove8,600 ft.27$12NoLet the gurgling Tarryall Creek sing you to sleep.
Twin Eagles8,600 ft.9$8NoMust haul or purify drinking water.
Happy Meadows7,900 ft.8$12NoSituated along the South Platte River.
Round Mountain8,500 ft.16$12YesDrinking water, vault toilet and trash pickup.
Springer Gulch8,300 ft.15$12YesSituated within the Elevenmile Canyon; water, tables, fire grates.
Riverside8,000 ft.19$12YesSituated within Elevenmile Canyon; large grassy meadow with little shade.

Eastward along summit ridgeEastward along summit ridge
Approaching the rocky summit areaApproaching the rocky summit area

Eleven Mile State Park
Colorado State Parks operates eight campgrounds near the Eleven Mile Reservoir, as well as 25 backcountry campsites accessible by foot or boat only. Visit this site ( for detailed information.

Weather & Seasons

Grassy SlopeGrassy Slope
East from the summit of Threemile MtnEast from the summit of Threemile Mountain

Summer: The route can be a bit hot and dusty in the summer, but the road should be dry and accessible and the breezes on top pleasant.

Spring: The snowpack is less deep here than in the high country and melts out faster than higher areas to the west. None-the-less, expect post-holing through unconsolidated snow drifts in the trees.

Fall: The aspen coating the slopes of this peak and surrounding neighbors make this area a golden-hued heaven in the fall.

Winter: Thanks to proximity to both US Hwy 24 Colorado Hwy 9, as well as to “primary dirt roads”, this peak is accessible year-round,except in blizzard conditions where drifting powder could block roads faster than highway crews can clear the snow.

Zone Forecast for Guffey, CO