Trail Description

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Diamond Lake is celebrated for its brilliant wildflowers, dramatic waterfalls, excellent fishing and backcountry camping. The lakeshore and adjacent meadows are easily explored, though you’ll likely get a bit wet doing so. Follow backcountry campsite trails across Diamond Lake’s outlet for panoramas of the basin and Continental Divide, or continue up the lake’s west shore to its lively inlet and an informal route leading to Upper Diamond Lake.

The trail begins on a moderate grade, rising steadily past the Indian Peaks Wilderness Backcountry board (.4 miles : 10,385’) to the first of several pitched switchbacks (.55 miles : 10,461’). Kaleidoscopic waves of summer wildflowers brighten the hillsides through which you’re passing. In .8 miles (10,595’) the trail levels across notably steep, open slopes with improving views (south) across the valley of Mount Neva (12,814’) and its distinguished ridgeline. A waterfall across this valley – Diamond Lake’s outlet - reveals its location and useful perspective on the general route you’ll take to reach it.

With little room to maneuver the trail negotiates the midsection of a precipitous waterfall (1 mile : 10,650’) and pitches up to the Arapaho Pass – Caribou Pass Trail junction (1.15 miles : 10,752’). Keep straight toward Diamond Lake. The trail glides gently back into serene forest, turns south in a move to cross the valley and drops briskly to The North Fork of South Boulder Creek (1.7 miles : 10,602’). Just upstream of this crossing is a turbulent waterfall worth a brief detour before making the final push to Diamond Lake.

Wood planks run over an open marsh just past the crossing (1.85 miles : 10,585’); once through, the trail turns sharply uphill in a dark, north-facing forest. This steep, twisting segment can be obscured by deadfall, runoff and lingering snow well into summer. After climbing 350’ in just .65 miles the trail emerges from dense timber and levels in a damp meadow on the northeast fringe of Diamond Lake (2.5 miles : 10,937’). Raised wooden planks skirt the meadow to the Devils Thumb Trail connection (2.55 miles : 10,939’), where travel eases through a sparse glade to Diamond Lake (2.65 miles : 10,940’).

GPS Coordinates - DATUM WGS84

• N39 59.714 W105 38.052 - Fourth of July Trailhead

• N40 00.036 W105 38.346 - .55 miles : Begin switchbacks

• N40 00.197 W105 38.616 - 1.0 miles : Cross mid-section of steep falls

• N40 00.252 W105 38.785 - 1.15 miles : Arapaho Pass Trail junction

• N40 00.191 W105 39.234 - 1.7 miles : Bridge over North Fork of S. Boulder Creek

• N40 00.102 W105 39.142 - 1.85 miles : Marshy travel beyond creek crossing

• N39 59.859 W105 38.979 - 2.25 miles : Steep climb to lake

• N39 59.701 W105 38.898 - 2.55 miles : Devils Thumb Trail junction

• N39 59.649 W105 38.945 - 2.65 miles : Diamond Lake

• N39 59.648 W105 38.876 - Diamond Lake : Backcountry Campsite #9

• N39 59.616 W105 38.861 - Diamond Lake : Backcountry Campsite #10

Worth Noting

• The Fourth of July Trailhead is named so because the lakes and high passes it accesses are typically not clear until after The Fourth of July. Locals have played on this name and claim its origin is tied to magnificent wildflower displays reminiscent of fireworks on The Fourth of July. Both interpretations are valid: anticipate lingering snow through mid-summer, and bar-none wildflowers once it clears.



• A false switchback bears left off-trail .75 miles from the trailhead. Take note, as it can easily be mistaken for the real trail on the return.



• Diamond Lake is stocked with Rainbow, Brook and Cutthroat trout.



• Diamond Lake is a popular destination reached by a heavily used trail artery. Get an early start to avoid peak-season congestion. Parking is limited and fills up very quickly on weekends.



• Road conditions between the Hessie Turnoff and 4th of July Trailhead can be rough. 4WD or all-wheel drive and high clearance is recommended.

Camping and Backpacking Information

• Permits are required for all overnight campers June 1 - September 15.



• Permits are required year-round for day and overnight use by large groups (8+) or organizational groups such as scouts, churches, schools and hiking clubs.



• Group size is limited to 12 people or people and packstock combined.



• Campfires are prohibited east side of the Continental Divide, as well as Caribou Lake, Columbine Lake, Gourd Lake, Crater Lake and in the Cascade Creek drainage above Cascade Falls.



• Pets must be on a handheld leash at all times.



• Camping is permitted only at designated campsites in the Diamond, Jasper, Crater and Caribou Lakes Backcountry Zones.



• Camping is prohibited in the Four Lakes Backcountry Zone (Mitchell, Blue, Long, Isabelle) May 1 - Nov 30.



• Camping is prohibited within 100’ of lakes, streams and trails.



• Packstock are prohibited in the Four Lakes Backcountry Zone, in the Cascade Backcountry Zone above Cascade Falls and on the Diamond Lake Trail #975.

Fishing Information

• Fishing is permitted at Diamond Lake with a valid Colorado state fishing license. Rainbow, Cutthroat and Brook Trout are stocked.

Directions to Trailhead

Diamond Lake is accessed from the Fourth of July Trailhead in the Indian Peaks Wilderness near Nederland, CO.

From downtown Nederland, go south on Highway 72 for .5 miles to County Road 130 and make a right. You will see a sign for Eldora Ski Resort at this junction. Continue on Highway 130 through the town of Eldora, just past which it becomes a dirt road (4 miles). Continue on the dirt road (past the Hessie Trailhead) another 4.8 miles and take the right fork at the Buckingham Campground up into the designated parking area. Though suitable for most 2WD cars in good condition, the road between the Hessie turnoff and Fourth of July Trailhead can be rough. High clearance vehicles are recommended.

Contact Information

Boulder Ranger District
2140 Yarmouth Avenue
Boulder, CO 80301

Visitor Information
Phone: 303.541.2500