- 20 miles west of Boulder
- 6.5 mile roundtrip
- 3 to 4 hours
- Trailhead Elevation:
- 10100 feet
- Elevation Change:
- 1800 feet
- June - October
From the Fourth of July Trailhead, the Arapaho Pass Trail climbs the wooded, northern slope of the North Fork, Middle Boulder Creek drainage. It soon enters the Indian Peaks Wilderness. This well-constructed trail traverses a sidehill, crossing steep slopes full of flowers in the early summer. After 1.2 miles, the Diamond Lake Trail #975 veers left where the Arapaho Pass Trail takes a switchback to the right. The trail climbs for another half mile, then follows a bench to the Fourth of July Mine (ele. 11,245), 2.1 miles from the trailhead. At the mine, the Arapaho Glacier Trail #905 intersects. Following this trail to the northeast (right) leads up to the Arapaho Glacier Overlook and eventually, down to Rainbow Lakes Campground. The Arapaho Pass Trail continues west on an old road 1.2 miles to Arapaho Pass (ele. 11,906), and the intersection with the Caribou Trail, #11. For a side trip, follow trail #11 west for about one-fourth mile to visit Lake Dorothy (ele. 12,061). The Caribou Trail continues on an impressive old road, blasted into a cliff, to Caribou Pass, but the road is sliding away. Some parts are now less than a trail width and not for the faint of heart. This road was supposed to cross the Divide, but Grand County never built its half, so the road runs out at Caribou Pass. A trail drops steeply down the far side and continues another 4 miles to Junco Lake Trailhead. The north slope traverse from Lake Dorothy to Caribou Pass has a very short season due to drifting snow. The Arapaho Pass Trail continues north (right) and drops 750 feet down a series of switchbacks to Caribou Lake, a popular camping area with limited, designated campsites. Backcountry camping permits are required. From Caribou Lake the trail continues to gradually lose elevation, passing through Coyote Park, past Wheeler Basin, and following Arapaho Creek to Monarch Lake.
Length: Fourth of July TH to Diamond Lake Trail 1.2; Arapaho Glacier Trail 2.1; Arapaho Pass - 3.3 miles; 4th of July TH to Arapaho Glacier Overlook – 3.9 miles; 4th of July TH to Monarch Lake TH - 13 ½ 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.
Continue westward as the pavement ends. Go right at the fork in the road.
Another 4 miles brings you to the Fourth of July Trailhead. This portion of the road is rough but passable in a passenger car.
This trailhead sees 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 if the trailhead parking lot is full.
For information on access from the Monarch Lake Trailhead on the western slope, contact the Sulphur Ranger District in Granby, 970-887-4100.