- 20 miles west of Boulder
- 14.2 mile roundtrip
- 7 to 9 hours
- Trailhead Elevation:
- 9000 feet
- Elevation Change:
- -3000 feet
- June - October
Devil's Thumb Trail crosses gently sloping terrain interspersed with steep stretches of trail. Along the way, it passes through forest, riparian woodland, and sunny, rocky slopes.
If you choose to skip driving through the water and park on the Fourth of July Road, take the quarter mile long Columbine Trail which starts at the bottom of the first hill, just before the water. It is a recently constructed trail that bypasses the flooded part of the road and comes in at the Hessie Townsite. From the Townsite, the road continues rough and with large mudpuddles another quarter mile to the Hessie Trailhead. There is very little parking at the trailhead itself.
From the Trailhead, cross the footbridge and take the Devil's Thumb Trail #902, which climbs steeply for about a half-mile on an old road. The Devil's Thumb Bypass turns right (north) in 0.8 miles, just before the bridge. Either the Devil's Thumb Trail or the Devil's Thumb Bypass will get you to the same destination - the distance is about the same either way. The bypass trail crosses open meadows to the north of the creek. The main trail follows an old road along the south side of the creek, staying right past junctions with the Lost Lake Trail #813, King Lake Trail #901 and Woodland Lake Trail #811.
It is 1.1 miles from the trailhead to the Lost Lake Trail junction, which is right at the top of a hill. From there it is a flat 0.2 miles to the King Lake Trail junction. The Devil's Thumb Trail enters the Indian Peaks Wilderness just beyond the King Lake Trail junction. It continues fairly level another 1.0 miles to the Woodland Lake Trail junction. In places, the creek has taken over the trail, so hikers have to follow social paths along the bank. The Devil's Thumb Bypass rejoins 200 yards beyond the Woodland Lake Trail.
After the trails rejoin, the old road begins to climb again. This stretch can be very wet, especially early in the summer, so some bypass social trails have developed. In 1.5 miles, the Diamond Lake Trail #975 forks right (north). It leads 3.7 miles up over the ridge past Diamond Lake to connect to the Arapaho Pass Trail 1.2 miles from the trailhead. From the Diamond Lake Trail junction it is another 0.6 miles to Jasper Lake.
Jasper Lake is surrounded on three sides with trees and a steep ridgeline to the north. It is a very popular camping area with limited, designated sites. There is no bridge across the spillway, but there is often a plank across a hundred yards downstream.
The trail continues another mile over a small ridge, north of a pond and up a slope to Devil's Thumb Lake. It lies directly below the vertically-walled Devil's Thumb. Past Devil's Thumb Lake, Devil's Thumb Trail wanders across open meadows near treeline, then makes several switchbacks up the steep side of a ridge to reach the Continental Divide. This steep portion of the trail holds snow and ice well into the summer and can be treacherous - crampons may be useful.
The Devil's Thumb Trail does not actually intersect the High Lonesome Trail #7 (part of the Continental Divide Trail) which is a couple hundred yards down the far side of the ridge, and not heavily traveled. From the top of the ridge it is another 0.6 miles downhill to the right (north) to Devil's Thumb Pass or 3 miles to the left (south) to the King Lake Trail #901. It is not difficult to eventually pick up the High Lonesome Trail from the Devil's Thumb Trail by just following the ridge, but finding the Devil's Thumb Trail from the High Lonesome Trail is more difficult. Note that the Devil's Thumb Trail does not climb to Devil's Thumb Pass (which has a snowfield most of the year), but ascends the ridge to the south. There is a large cairn where it tops out, just south of the high point at the ridge intersection. To access Devil's Thumb from 4th of July Trailhead, follow the Arapaho Pass Trail #904 for 1.2 miles, take the Diamond Lake Trail #975 3.7 miles more past Diamond Lake and over the ridge to hit the Devil's Thumb Trail 0.6 miles east of Jasper Lake. Turn right (west) to reach the lakes and pass.
Length: Hessie Trailhead to Jasper Lake - 4.5 miles; to Devil's Thumb Lake - 5.5 miles; to Continental Divide - 6.5 miles; to Devil's Thumb Pass 7.1 miles. DISTANCES ARE ONE-WAY.
From Nederland, west of Boulder, turn west on paved County Road 130, following signs for Eldora Ski Resort and the town of Eldora.
Go through the town of Eldora.
At the end of town, continue westward as the pavement ends, following to the left at the next road fork for Hessie Trailhead.
A right at this fork and another 4 miles would bring you to the Fourth of July Trailhead. (Devil's Thumb Trail is accessible from the 4th of July Trailhead, however, the more direct route is through Hessie.)
Both of these Trailheads see extremely high use, especially on weekends, and parking is limited. Plan to arrive early and watch for signs along the road indicating legal parking spots.
Please note that a stretch of the road from County Road 130 to the Hessie Trailhead is a cobblestone creek bed. It carries water year round, and runs heavily in the early summer. It is passable by 2WD vehicles, however, high clearance is recommended. There is a parallel trail so hikers can bypass the water.