- 22 miles west of Boulder
- 15.6 mile roundtrip
- 1 day
- Trailhead Elevation:
- 10000 feet
- Elevation Change:
- 2700 feet
- June - October
Trail #905 leads northward from the trailhead, entering the Indian Peaks Wilderness before long. It climbs through the woods for about two miles, then comes out onto the open tundra with a fine view into the City of Boulder Watershed, including Silver Lake, Island Lake, Goose Lake, and Triple Lakes. This is private property, do not trespass. After more switchbacks, the trail crosses a col to the south side. From here it is little traveled, and can be obscure in places as it continues gently along the side of the ridge. At the highest point on the trail (6.0 miles from the trailhead), the hiker is offered a spectacular overlook of the Arapaho Glacier, and the South Arapaho (13,397 feet) and North Arapaho (13,502 feet) Peaks.
Although no official trail exists, it is possible to ascend S. and N. Arapaho Peaks by following the ridge above the glacier. (The climb to South is straightforward rock-hopping. From South to North, some scrambling is necessary, and there is some exposure. This does not require technical climbing/equipment, but the narrow ridge is steep and rocky. Use caution!) Past the glacier overlook, the Arapaho Glacier Trail descends 1,300 feet down a series of switchbacks to intersect the Arapaho Pass Trail #904 at the Fourth of July Mine. Arapaho Pass is 1.2 miles farther west.
Length: Arapaho Glacier Trail: Rainbow Lakes Trailhead to Arapaho Glacier Overlook - 6.0 miles; to Fourth of July Mine - 7.8 miles; DISTANCES ARE ONE-WAY.
Map + Directions
Approximately 7 miles north of Nederland, on Highway 72, turn west onto Rainbow Lakes Road (a.k.a. County Road 116, and FDR 298).
Look for the University of Colorado Mountain Research Station sign. Drive past the Sourdough Trailhead, and after approximately 1 mile turn left (south) on FDR 298, following signs for Rainbow Lakes Campground.
This is a rough, native-surfaced road and it is about 5 miles from Hwy. 72 to the trailhead. High clearance vehicles are recommended, although passenger cars and other vehicles, driven slowly, should have no problem negotiating the road.
Trailhead parking is at the west end of the Rainbow Lakes Campground.