Boulder, CO: Isabelle Glacier

Trek past cloud-scraping peaks and shimmering lakes en route to breathtaking views of the Isabelle Glacier on this 8.1-miler in the untamed Indian Peaks Wilderness.

The Indian Peaks Wilderness owes much of its stunning geography—pristine turquoise lakes, magnificent U-shaped valleys, regal granite cirques, and craggy sawtooth peaks—to the glaciers that molded its landscapes as recently as 15,000 years ago. Pay homage to the remnants of one such glacier while taking in high-alpine scenery on this 8.1-mile out-and-back to Isabelle Glacier.

Nestled between Niwot Ridge to the south, the Pawnee Peaks to the north, and a towering cirque to the west, this route offers a virtual greatest-hits collection of southern Rocky Mountain topography in one short, moderately-challenging dayhike. From the trailhead, pick up the Pawnee Pass Trail and wind through spruce forest toward the well-trafficked Long Lake. At mile 0.3, bear right to stay on Pawnee Pass Trail and circumvent the lake's scenic northern shore.

After passing the 40.5-acre lake, continue winding through forests and meadows on the relatively flat trail before climbing a series of mildly-strenuous switchbacks around mile 1.6. After a half-mile ascent, grab your first eyeful of the stunning landscape ahead: Lake Isabelle backdropped by the formidable Apache, Navajo, and Shoshone peaks in the distance. Bearing left to hit the Isabelle Glacier Trail, trek past the northern shores of the lake on a rocky trail before heading uphill at mile 2.8.

At the top of the ascent, cruise through a marshy meadow toward a third lake and the hike's hardest section: a 0.4-mile climb, gaining nearly 500 feet, toward the glacier. The reward at the top of the scramble is plain to see: close-up views (and access) to Isabelle Glacier and the surrounding cirques to the west, and a revealing panorama of the valley you just passed through to the east.

-Mapped by Genny Fullerton and Elisabeth Kwak-Hefferan

Hike Isabelle Glacier

Order the USGS topo quads listed above at
Order a custom map of this route by selecting the "Print MyTopo" option in the left-hand menu bar.

PERMITS: For permiting information, go to the Indian Peaks Wilderness page on the Arapaho & Roosevelt National Forests website.

CONDITIONS: Check weather at Ward, CO (80481) Weather

INFO: For more information, go to the Indian Peaks Wilderness page on the Arapaho & Roosevelt National Forests website.

CONTACT: 2150 Centre Avenue, Building E, Fort Collins, CO 80526; (970) 295-6600


Neptune Mountaineering, Inc.
633 South Broadway #A
Boulder, CO
(888) 499-8866 ‎

1789 28th St.
Boulder, CO
(303) 583-9970


Millsite Inn
44365 CO 72
Ward, CO
(303) 459-3308 ‎

Gold Hill Inn
401 Main St.
Gold Hill, CO
(303) 443-6461

Mountain Sun Pub & Brewery
1535 Pearl St.
Boulder, CO
(303) 546-0886

Trail Facts

  • Distance: 13.0



Location: 40.07794, -105.584493

From the parking area, head west on Pawnee Pass Trail, trekking over relatively flat terrain through a forest of Engelmann spruce.


Location: 40.075905, -105.586989

Just about 0.3 mile from the trailhead, the path meets up with the South St. Vrain Creek. At the Y-junction, bypass the Jean Lunning Trail to continue on the Pawnee Pass Trail.


Location: 40.074302, -105.59233

Enjoy the views of Long Lake as you skirt its northern shores. At such a close proximity to the trailhead, the lake is a popular destination for hikers of all fitness levels: expect to hit some traffic on this section of the trail.


Location: 40.070378, -105.601358

Bear right to stay on Pawnee Pass Trail; the trail starts heading uphill.


Location: 40.069073, -105.610027

Continue pushing west as the trail transforms into a series of moderately-challenging switchbacks. Lake Isabelle lies just over the next ridge.


Location: 40.070368, -105.61456

Continuing your westward push, catch first views of the glacier-fed Lake Isabelle framed by a towering, snow-patched granite cirque. At the Y-junction, bear left to pick up Isabelle Glacier Trail. The rocky trail crosses many small streams as it winds around the lake.


Location: 40.070267, -105.615907

This high-alpine environment is bustling with wildlife. Keep your eyes peeled for the pika and marmots that make their home in the area's rocky terrain.


Location: 40.070674, -105.617151

Descend toward the shore of Lake Isabelle; the trail becomes smoother. Fed by snow and glacial runoff, Isabelle's water levels are highest during spring snow-melt season. Plan accordingly if you're looking to catch the lake in its prime.


Location: 40.068712, -105.623116

Leave Lake Isabelle (and the crowds) and ascend toward a ridge overlooking both lakes. In nearly 300 feet, you'll hit a glacier-fed cascade (you'll hear it before you reach it).


Location: 40.067029, -105.628248

The trail steepens here as you climb toward spectacular views of Lake Isabelle.


Location: 40.065206, -105.630911

As the trail levels out and crosses into a marshy high-alpine meadow, take in views of the majestic cirque punctuated by the toothy Shoshoni, Navajo and Apache peaks. Rock hop across a little stream as you continue pushing toward the glacier.


Location: 40.061749, -105.63716

Take in serene views of a third, smaller glacial lake as you gear up for the hike's final (and most strenuous) section: a precipitous 0.4-mile scramble, gaining 520 feet, toward Isabelle Glacier.


Location: 40.063007, -105.640822

After finishing the hike's hardest stretch, savor awe-inspiring panoramas of Isabelle Glacier and Lake Isabelle. Access to the glacier is less than 300 feet away.


Location: 40.063556, -105.642107

If conditions are safe, step out onto the glacier and play around. Enjoy the fruits of your labor before turning around and re-tracing your path back to the trailhead.

Isabelle Glacier Trail

Location: 40.070428, -105.614158

Pick up the Isabelle Glacier Trail right before reaching Lake Isabelle.

Eldermann Forest Creek

Location: 40.075543, -105.591037

The hike begins by rolling through a mellow spruce forest.

Peaks Vista

Location: 40.070568, -105.602936

The breathtaking alpine scenery appears early and often on this route.

Fall Colors

Location: 40.070543, -105.602624

Autumn transforms the valley into a 360-degree fireworks display.

Stream Crossing

Location: 40.070354, -105.612388

Hiking on, you'll cross many small, snow-fed streams, especially during spring.

Rocky Section Of Trail

Location: 40.070398, -105.616336

The path becomes rockier as it skirts the doge of Lake Isabelle.

Glacial Waterfall

Location: 40.068263, -105.624189

This cascade on the South St. Vrain Creek carries water from the Glacier and surrounding snow-covered peaks into the lakes below.

Trail Steepens

Location: 40.066807, -105.629382

The trail steepens here as you climb toward spectacular views of Lake Isabelle.

High-Alpine Meadow

Location: 40.065231, -105.630627

Cross through a marshy meadow offering fantastic views of the surrounding peaks as you approach the cirque.

Granite Peak

Location: 40.062263, -105.633116

The trail winds around this towering granite peak.

Small Lake

Location: 40.061782, -105.636849

This smaller, unnamed lake rests just before your final ascent toward the glacier.

Climbing to Isabelle Glacier

Location: 40.062394, -105.638335

Catch birds-eye views of the lake you just passed while scrambling up the hike's final climb.

Trail's End

Location: 40.063457, -105.641613

Savor views of spectacular landscapes after completing the last section of the hike.