Overview
Pawnee Pass is the signature route in Indian Peaks Wilderness for hikers who want a full day in alpine terrain without committing to an overnight backpack. The trail follows the Long Lake and Lake Isabelle corridor, two of the most scenic valleys in the Front Range, before climbing steeply to the Continental Divide at 12,541 feet. From the pass, the view west opens onto Grand County and the headwaters of the Colorado River drainage - a reminder that the water falling on this side of the mountain ends up in the Pacific Ocean while the water on the east side flows to the Gulf of Mexico.
At 12 miles round trip with 2,800 feet of gain, this is a long, demanding day hike. The approach miles through the Long Lake basin are relatively gentle, giving hikers time to acclimatize before the steeper upper section. The final mile to the pass gains the bulk of the elevation in a direct climb up a headwall. It's not technical, but it's relentless.
Dogs are allowed on leash throughout. Overnight camping requires an Indian Peaks Wilderness permit, but day hikers can complete the out-and-back without one beyond the standard Brainard Lake Recreation Area fee. Review checking conditions before you go for weather, road, and current permit information before your trip.
The Route
Miles 0 to 1.5: Long Lake Basin. The trail leaves Long Lake Trailhead heading southwest through subalpine terrain. Long Lake comes into view quickly on the right, its surface reflecting the peaks above. The grade is gentle here, and the trail is wide and well-defined. This section is popular with families and casual hikers who turn around at Long Lake - expect foot traffic on summer weekends.
Miles 1.5 to 3.5: Lake Isabelle Approach. Beyond Long Lake, the trail narrows and begins to gain elevation more steadily. The basin opens up, with Shoshoni Peak and Navajo Peak visible ahead. Lake Isabelle appears at about 11,000 feet - a large, impossibly blue alpine lake ringed by granite walls and late-season snowfields. This is a natural stopping point for those not continuing to the pass. The setting here is outstanding on its own.
Miles 3.5 to 5.0: Isabelle Glacier Basin. Above Lake Isabelle, the trail enters the upper basin below Isabelle Glacier. The glacier has retreated significantly in recent decades, but permanent snowfields remain visible on the headwall above. The trail crosses boulder fields and patches of alpine tundra. Cairns mark the route where the trail surface becomes less defined on rock slabs.
Miles 5.0 to 6.0: The Headwall and Pawnee Pass. The final mile gains most of the remaining elevation in a direct climb up the east face of the headwall. Switchbacks help, but the grade is steep and sustained. The surface is a mix of loose scree and solid rock. Near the top, the trail emerges onto the Continental Divide at Pawnee Pass. The west-facing views open suddenly and dramatically: the mountains of Grand County, distant mesas, and the long valleys leading toward Granby.
Descent: Return the same way. The headwall section is the trickiest on the descent - loose rock and steep terrain demand careful footing. The boulder field sections above Lake Isabelle require attention. Once you're back in the Long Lake basin, the descent to the trailhead is straightforward.
Permits and Fees
The Brainard Lake Recreation Area day-use fee ($15/vehicle, as of 2026) is required at Long Lake Trailhead. An America the Beautiful pass does not waive this specific area fee.
Overnight camping in Indian Peaks Wilderness requires a reservation ($6 per group per night) through Recreation.gov. Permits for popular summer weekends sell out quickly after the reservation window opens each spring. Popular backpacking destinations in the wilderness from Pawnee Pass include Pawnee Lake on the west side of the pass and camping zones in the Isabelle basin on the east side. Check recreation.gov for current rules and availability. Our national forest camping permit guide covers the general reservation process.
Day-use permits for Indian Peaks Wilderness itself are not currently required, but regulations have been evolving in response to heavy use. Verify the current system through the Boulder Ranger District before your visit.
When to Hike
Mid-July through September is the main window. Pawnee Pass holds snow well into July in typical years, and the headwall can be icy and dangerous in early season without an ice axe and the skills to use one. After a heavy snow year, the approach may be passable by late June but the pass itself could remain snow-covered into August.
September is the best month for those who can manage the timing. Crowds are much smaller after Labor Day, the weather tends toward stable mornings (though afternoon storms remain possible), and the light in the alpine basins has a clarity and warmth that summer haze obscures.
Morning starts are important. Colorado afternoon thunderstorms are a serious hazard above treeline. The pass itself is the most exposed point on this route. Plan to reach the pass by 11 AM or noon at the latest and be well below treeline before 2 PM. A 5 or 6 AM departure from the trailhead is appropriate for summer hiking.
What to Bring
Water: The Long Lake and Isabelle basins have water sources accessible for filtering, but above Lake Isabelle the options thin out. Carry treated water from the trailhead. Many hikers bring 2 to 3 liters for this distance; individual needs vary.
Wind and cold layers: The pass is fully exposed and frequently windy. A wind shell is worth carrying even on warm days. At 12,541 feet, temperatures drop quickly when clouds move in.
Trekking poles: The boulder fields above Lake Isabelle and the steep headwall descent are significantly easier with poles.
Navigation: Download an offline map through Gaia GPS, AllTrails, or similar before leaving cell service. The route is well-marked through the Long Lake basin but becomes more reliant on cairns in the upper section.
Leave No Trace kit: This is one of the most visited wilderness corridors in the country. Pack out everything. The alpine tundra here is fragile and recovers slowly from damage.
Trailhead Access
Long Lake Trailhead is at the end of Brainard Lake Road, about 5 miles west of Ward, Colorado. From Boulder, the drive is approximately 40 miles and takes about an hour. From Denver, plan on 1.5 hours. The road to the trailhead is paved to the recreation area entrance and well-maintained gravel beyond.
The Long Lake Trailhead shares access with the Mitchell Lake Trailhead and the main Brainard Lake parking area. The combined lots hold a large number of vehicles but still fill completely by mid-morning on summer weekends. Arrive by 6 or 7 AM on weekends to find a space. There are no shuttles from external points currently, though the forest service has piloted mandatory shuttle systems from overflow areas on peak days - check current procedures with the Boulder Ranger District.
No cell service at the trailhead. Vault toilets are available. There is no water at the trailhead; fill up before leaving town.
For a shorter and easier introduction to the same Brainard Lake landscape, the Long Lake Loop covers the lower section of this trail in a 2.6-mile circuit before heading up. The Blue Lake Trail from Mitchell Lake Trailhead is another solid day-hike option in the same area for those wanting a moderate alternative.