Diamond Lake Trail


Photo of Diamond Lake in June frozen and covered with snow

The Arapaho Pass Trail enters the Indian Peaks Wilderness and climbs for 1.2 miles to the Diamond Lake Trail.

The Diamond Lake Trail forks left from the Arapaho Pass Trail and drops elevation for a half-mile before crossing the North Fork of Middle Boulder Creek. Diamond Lake is located a mile further uphill from the bridge and scenic waterfall. This stretch of trail is on a northeast-facing slope and holds snow long after the Arapaho Pass Trail has melted dry. Turn west on a marked side trail to Diamond Lake.

Continuing straight and passing the turnoff to Diamond Lake, the main trail continues for 2.4 miles, and climbs up to cross the ridge just above tree line. The return to tree line may be difficult to find - watch for rock cairns at the edge of the trees. The Diamond Lake Trail ends at Devils Thumb Trail.

Click here for a trail description.

At a Glance

Permit Info: This trail lies within the Indian Peaks Wilderness Area:
  • Camping permits required for all overnight trips between June 1 and September 15. Overnight permits cost $5 per group, per trip from June 1 through September 15.
  • Organized groups are required to have a permit for both camping and day-hiking year round. Day-hiking permits are free.
Usage: Heavy
Restrictions: Indian Peak Wilderness restrictions apply:
  • Motorized and mechanized vehicles are prohibited.
  • Pets must be on a hand-held leash at all times.
  • Campfires prohibited.
  • Campsites must be at least 100 feet away from water and trail.
  • Group size is limited to 12 (people and livestock combined).
Fishing and hunting: permitted in accordance with regulations established by the Colorado Parks & Wildlife.
Closest Towns: Nederland, Colorado
Water: Lakes and streams; treat water for drinking.
Restroom: Practice Leave No Trace principles
Operated By: U.S. Forest Service
Information Center: Boulder Ranger District, 2140 Yarmouth Ave, Boulder, CO 80301, Phone 303-541-2500, Fax 303-541-2515; Contact Us

General Information


From Nederland, head south on Colorado Highway 119 for 0.5 miles. Turn west onto Boulder County Road 130 (signed for Eldora Ski Resort). Stay on the main road through the town of Eldora. Once the pavement ends continue another five miles to the Fourth of July Trailhead. This portion of the road is rough but passable in a passenger car during the summer months. This trailhead is extremely busy, especially on weekends, and parking is limited.



Show detail SHOW


Hide detail HIDE

Day Hiking

This trail is within the Indian Peaks Wilderness Area, connecting between Arapaho Pass Trail and Devils Thumb Trail, passing by Diamond Lake along the way.

Difficulty Level: Intermediate


This trail is within the Indian Peaks Wilderness Area, where permits are required for camping June 1 - September 15. Those camped at Diamond Lake must have a permit for a designated campsite.

Fire InformationCampfires are prohibited year-round.
Difficulty Level: Intermediate

Winter Sports

Show detail SHOW
Areas & Activities


  Area/Length : 
Fourth of July Trailhead to: Diamond Lake - 2.6 miles; Devils Thumb Trail - 5.0 miles. (One way)

  Elevation : 
10,100' - 11,400'