Green Mountain Trail (Boulder)

Green Mountain is the 8,144-foot summit behind the Flatirons, the peak Boulder hikers use as a training climb before work and the one with the best summit of the three above town: a rock top with a bronze peak-finder that names everything from Longs Peak to Pikes Peak. From Gregory Canyon the round trip is 5.6 miles with 2,400 feet of gain, and there are three ways up.

From the Gregory Canyon trailhead, the Gregory Canyon trail climbs a mile up the canyon on rock steps to a saddle and the Green Mountain Lodge, a stone shelter. From the lodge, the E.M. Greenman trail climbs through the woods on the mountain's north side, joining the Ranger trail for the final switchbacks to the summit; it is the most direct line. The Saddle Rock trail, steeper and rockier, leaves the Gregory Canyon trail lower down and climbs past the Saddle Rock outcrop to meet Greenman near the top, and it makes a good loop.

The summit is a jumble of boulders with the peak-finder disk on the highest one, and the view runs from the plains to the Indian Peaks and Longs. Return by whichever trail you did not take up. Bear Peak and South Boulder Peak are reachable along the ridge for a much longer day.

Gregory Canyon trailhead is at the bottom of Flagstaff Road, just above the Chautauqua area on Baseline Road. The small lot charges a daily fee for vehicles not registered in Boulder County, payable at the station, and fills by 7 AM on weekends year-round. Parking along Baseline and at Chautauqua adds a short walk; the Chautauqua park-to-park shuttle runs on summer weekends. No permit.

Dogs are allowed on leash, or off leash with a Boulder voice-and-sight tag on the trails that permit it; the signs at each junction say which. From August 15 to December 1 dogs must be leashed on parts of the Gregory Canyon, Saddle Rock, Amphitheater, and Bluebell-Baird trails because bears feed there before denning. The climb is steep enough that this is a trail for older kids. Carry water; there is none on the mountain. The rock steps in Gregory Canyon are hard on knees on the way down, which is a reason to descend Greenman. Boulder is at the trailhead. The Boulder hikes page lists the Flatirons trails, and Bear Peak and South Boulder Peak are the neighbors.