Lake Isabelle, Brainard Lake Recreation Area, Indian Peaks Wilderness Area, Colorado
Lake Isabelle - 4.2 miles
Brainard Lake Recreation Area

Round-Trip Length: | 4.2 miles |
Start-End Elevation: | 10,515' - 10,868' (10,903' max elevation) |
Elevation Change: | +353' net elevation gain (+438' total roundtrip elevation gain) |
Skill Level: | Easy-Moderate |
Dogs Allowed: | Yes |
Bikes Allowed: | No |
Horses Allowed: | No |
Related Trails: |
Lake Isabelle - 4.2 Miles Round-Trip
Lake Isabelle is located 2.1 miles from Long Lake Trailhead in the Brainard Lake Recreation Area of the Indian Peaks Wilderness. It lies at treeline in a stunning alpine valley framed by Navajo (13,409'), Apache (13,441') and Shoshoni (12,967') peaks.
The trail continues 2.3 miles to its source at Isabelle Glacier (12,025') at the head of the valley. Visitors will enjoy abundant flowers, good fishing and mild grades on the hike to Lake Isabelle:
A level path follows the north shore of Long Lake beneath uniform spruce to the first of two connections with the Jean Lunning Trail (.2 miles : 10,524').
It undulates mildly past a second Jean Lunning connection (1.2 miles : 10,674') to a clearing with a glimpse of the upper valley (1.6 miles : 10,716').
The trail steepens (1.85 miles) in a thinning forest to Lake Isabelle and the Pawnee Pass Trail split (2.1 miles : 10,892'). A social trail leads south across the outlet stream, where you'll likely find a bit more privacy and room to explore.
The main trail continues west along Isabelle's north shore with access to a number of outcrops, viewpoints and room for anglers. Isabelle Glacier is 2.3 miles and 1140' up from Lake Isabelle.
For an aerial view, climb a few hundred yards up the Pawness Pass Trail, which splits north through treeline over the lake basin. It continues 2.45 miles and 1650' to Pawnee Pass on the Continental Divide. Consider returning via the Jean Lunning Trail, which loops around Long Lake with many good access points for anglers. This adds nominal elevation gain and .4 miles to the return hike.
Note: Lake Isabelle is drained every year in late July / early August so be sure to call the Boulder Ranger district to make sure the lake will be full for your hike.
Interactive GPS Topo Map
Key GPS Coordinates - DATUM WGS84
- N40 04.674 W105 35.077 — 0.0 miles : Long Lake Trailhead
- N40 04.550 W105 35.220 — .2 miles : Jean Lunning Trail junction #1
- N40 04.223 W105 36.083 — 1.2 miles : Jean Lunning Trail junction #2
- N40 04.167 W105 36.716 — 1.85 miles : Begin moderate switchbacks
- N40 04.225 W105 36.875 — 2.1 miles : Lake Isabelle and Pawnee Pass Trail junction
Worth Noting
- Isabelle Lake and Isabelle Glacier were named by Fred Fair, a Boulder City engineer who discovered the glacier in the early 1900s. He named both after his wife. When he died in 1935, his ashes were scattered over Isabelle and Fair glaciers.
- This is a heavily used trail and parking is limited. Get an early start to secure parking and avoid crowds.
- Fishing regulations are specific and change seasonally. Call ahead for current restrictions.
- Lake Isabelle is drained every year in late July / early August which significantly affects the trail experience. Please contact the Boulder Ranger District before your hike to ensure the lake is still full.
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 4 Lakes Backcountry Zone (Mitchell, Blue, Long, Isabelle) May 1 - Nov 30.
- Camping is prohibited within 100' of lakes, streams and trails.
- Packstock is prohibited in the Four Lakes Backcountry Zone, in the Cascade Backcountry Zone above Cascade Falls and on the Diamond Lake Trail #975.
Rules and Regulations
- There is an $11 fee to enter the Brainard Lake Recreation Area. Use the self-service pay station if no attendant is on duty. Fees, Parking, Pet, Camping and Trespassing regulations are strictly enforced.
- Dogs must be leashed at all times on trails within the Brainard Lake Recreation Area.
Directions to Trailhead
The Long Lake Trailhead is located within the Brainard Lake Recreation Area off of CO 72 (12 miles north of Nederland, just north of the town of Ward).
From Highway 72, turn west on Brainard Lake Road. In 2.6 miles you'll reach a pay station. Use the self-service pay station if no attendant is on duty. Continue another 3.2 miles on the paved road to the Long Lake Trailhead. This road may be closed at the halfway point from late October through late June or early July (depending on snow).
Long Lake can also be reached via the Niwot Cutoff Trail from the Niwot Cutoff Trailhead near the Niwot Mountain Picnic Area on the west end of Brainard Lake.
Contact Information
Boulder Ranger District
2140 Yarmouth Avenue
Boulder, CO 80301
303.541.2500
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