Crosier Mountain Trail

Crosier Mountain is a 9,250-foot forested summit between Glen Haven and Drake in the North Fork of the Big Thompson, outside Rocky Mountain National Park, with a summit view of Longs Peak and the Mummy Range and no permit, fee, or shuttle. Three trails reach it; the Glen Haven trail is the shortest and the one listed here, about 7 miles round trip with 2,000 feet of gain.

From the Glen Haven trailhead, the trail climbs steeply from the start through ponderosa and Douglas fir on the north side of the mountain, switchbacking up a drainage with the grade rarely easing for the first 2 miles. It passes through aspen groves and old meadows on the mountain's shoulder and joins the Garden Gate trail from the east.

The combined trail climbs the last half mile to the summit, a rocky clearing at 9,250 feet with Longs Peak, Mount Meeker, and the Mummy Range to the west and the plains to the east. The Garden Gate trail, 2.2 miles up County Road 43 from Drake, is the longest and gentlest route, about 4 miles each way; the Rainbow trail, 5.5 miles from Drake, is the steepest of the three. Return the same way or make a point-to-point with two cars.

Glen Haven is 7 miles northeast of Estes Park on Devils Gulch Road (County Road 43). The Glen Haven trailhead is a small lot at the west edge of the village, signed, with room for a dozen cars; the Garden Gate trailhead, about 5 miles back toward Drake, holds six vehicles with no trailer parking. No fee or permit. Glen Haven has a general store and no toilet at the trailhead.

Dogs are allowed and should be leashed; the trail is on Roosevelt National Forest. A woman was killed by a mountain lion on the Crosier Mountain trail on January 1, 2026, and the trail reopened with permanent warning signs; hike with company, keep dogs leashed and children close, and never run from a lion. The steady steep grade is why the Glen Haven route is not marked kid-friendly; the Garden Gate trail suits older kids. Carry two liters; there is no water on the mountain. Mountain lions and bears live here. Estes Park is 15 minutes away with every service. The Estes Park hikes page covers the park trails that need permits, and this is the one that does not.