Long Lake Trailhead: Brainard Lake's Gateway to Lake Isabelle and Pawnee Pass

The Long Lake Trailhead sits at the far west end of the Brainard Lake Recreation Area, about an hour up the mountain from Boulder, and it's the single best jumping-off point in the Indian Peaks Wilderness. From a small lot at roughly 10,500 feet, you can walk fifteen minutes to a flat, photogenic alpine lake, push a little farther to Lake Isabelle under the Continental Divide, or grind all the way up to Pawnee Pass at 12,550 feet. Same parking spot, four completely different days out.

Here's the catch that trips up most first-timers. You can't just drive up and park in summer anymore. The Long Lake Trailhead sits behind a timed-entry gate from mid-June through October, and the lot is tiny, so you need a reservation and an early alarm. Get those two things right and this is one of the easiest ways in Colorado to reach real high-country scenery without a permit lottery or a 4 a.m. start.

This guide covers the 2026 reservation rules, how to find the trailhead and where to park, all four hikes broken down by distance and difficulty, the moose you'll probably see, and what to pack for a day this high.

Lake Isabelle below the Continental Divide, reached from the Long Lake Trailhead in the Indian Peaks Wilderness
Lake Isabelle sits under the Continental Divide, a short walk past Long Lake from the trailhead.

Quick Stats {#quick-stats}

Trailhead elevation: about 10,500 feet
Location: west end of Brainard Lake Recreation Area, Indian Peaks Wilderness, Roosevelt National Forest, near Ward
Drive from Boulder: roughly one hour
2026 season: recreation area open June 12 to October 1; the upper lots (Long Lake, Mitchell Lake, Niwot) open July 1
Fee: $16 per vehicle, timed-entry, booked on Recreation.gov
Trails from here: Long Lake loop, Lake Isabelle, Isabelle Glacier, Pawnee Pass
Dogs: allowed on a hand-held leash May 1 through November 14

Do You Need a Reservation for the Long Lake Trailhead? {#reservation}

Yes, if you want to drive in during the summer season. From June 12 through October 1, 2026, every vehicle entering the Brainard Lake Recreation Area needs a timed-entry reservation, and Recreation.gov is the only legitimate place to get one. Day-use tickets cost $16 per vehicle and release on a rolling window, with new dates opening 14 days ahead at 8 a.m. Mountain Time. You can hold up to two reservations per day, so it pays to set a calendar reminder and book the moment your date opens.

A few details that catch people off guard. The reservation gets your car past the entrance station; it does not guarantee a spot in the Long Lake lot specifically, which is why arriving early still matters. The upper trailheads, including Long Lake, don't open until July 1, so a June trip means starting from the lower Gateway Trailhead and adding miles. And if the timed slots are gone, you can still walk or bike in from the Gateway Trailhead without a reservation, which adds a couple of miles each way but costs nothing.

If you're weighing this area against Rocky Mountain National Park next door, our RMNP vs Indian Peaks Wilderness comparison lays out the permit and crowd trade-offs. The short version: Brainard's system is a little friendlier than the Bear Lake corridor.

Brainard Lake with the Indian Peaks rising behind it near the Long Lake Trailhead
Brainard Lake itself is a short drive below the Long Lake Trailhead, with the Indian Peaks filling the skyline.

Getting to the Long Lake Trailhead {#getting-there}

From Boulder, take Canyon Boulevard (Highway 119) up Boulder Canyon to Nederland, then head north on the Peak to Peak Highway (Highway 72) for about 12 miles to the town of Ward. The Brainard Lake turnoff is marked just north of Ward. Follow the paved road past the entrance station, around Brainard Lake, and continue to the road's end, where the Long Lake and Mitchell Lake lots sit side by side. Plan on roughly an hour of driving from Boulder, more from Denver.

The Long Lake lot is small and fills fast. On summer weekends it can be full by 7 a.m., sometimes earlier. Get there at first light, or plan a weekday. If the lot's full when you arrive, the Mitchell Lake lot next door and the larger Brainard Lake day-use areas below give you backup parking, though they add a walk. For a wider look at how mountain lots fill and when to show up, see our guide to Colorado trailhead parking.

The Four Hikes From the Long Lake Trailhead {#the-hikes}

The reason this trailhead is so good is that one parking spot feeds four very different hikes. Pick the one that matches your legs and the weather.

Long Lake Loop (easy, about 2.5 miles)

Long Lake is a quarter mile from the lot, and the full loop around it on the Jean Lunning Trail runs roughly 2.5 miles with almost no elevation gain. This is the family hike, the recovery-day hike, the hike for anyone still getting used to the altitude. The trail hugs the shoreline through spruce and fir, and the far end opens onto a straight-shot view of Niwot Ridge, Navajo Peak, and Apache Peak reflected in the water on a calm morning. If you only have an hour or you've got kids along, this is the one.

Lake Isabelle (moderate, about 4.5 miles round trip)

Keep going past Long Lake on the Pawnee Pass Trail and you climb gently to Lake Isabelle, roughly 4.5 miles round trip with about 600 feet of gain. This is the trip most people come for, and it earns the reputation. Isabelle sits in a rock bowl directly beneath the divide, with Shoshoni and Apache peaks stacked behind it. One thing worth knowing: Isabelle is a reservoir, and it gets drawn down for irrigation in late summer. Come June through mid-August for a full lake; by September it can look more like a mudflat with a creek running through it. For more high-country water like this, our roundup of the best alpine lakes in Colorado has plenty of company.

Lake Isabelle under Shoshoni and Apache peaks in the Indian Peaks Wilderness
Lake Isabelle sits in a rock bowl beneath the divide, about 4.5 miles round trip from the Long Lake Trailhead.

Isabelle Glacier (hard, about 8 miles round trip)

For a longer day, the trail continues past Lake Isabelle and climbs into the basin toward the small remnant of Isabelle Glacier, roughly 8 miles round trip. The upper section gets rocky and steep, and snow can linger here well into July, so bring traction early in the season. The payoff is a wild cirque of waterfalls, tarns, and the divide towering overhead, with a fraction of the foot traffic you'll see down at Isabelle.

Pawnee Pass (hard, about 9.5 miles round trip)

The big one. From the trailhead, the Pawnee Pass Trail switchbacks up to the top of the Continental Divide at 12,550 feet, about 9.5 miles round trip with around 2,100 feet of gain. The pass marks the boundary between the Roosevelt and Arapaho national forests, and the view west into the Lake Granby country is worth every switchback. This is a full alpine day, so start early and watch the sky. Strong hikers sometimes drop off the far side to Pawnee Lake or link this into a longer traverse toward Monarch Lake. If you're new to hikes above 12,000 feet, read up on altitude sickness before you go.

The Isabelle Glacier basin high on the Continental Divide above the Long Lake Trailhead
The upper basin toward Isabelle Glacier and Pawnee Pass holds snow into July and rewards the longer climb.

Wildlife: Moose and More {#wildlife}

The stretch of the South St. Vrain valley between Long Lake and Lake Isabelle is prime moose habitat, and sightings here are common enough that you should plan for one. Moose look slow and calm right up until they aren't. Give any moose at least 50 feet, more if there's a calf, and back off the way you came if one is on the trail. Never get between a cow and her calf for a photo.

You'll also share the tundra with yellow-bellied marmots, pikas darting through the talus, and the occasional black bear. If you're camping overnight in the Four Lakes zone here, a bear canister is required, not optional, and rangers do check. The Indian Peaks section of our best hikes in Indian Peaks Wilderness guide covers the overnight permit and canister rules in more detail.

Best Time to Hike {#when-to-go}

The upper trailhead opens July 1, and that's roughly when the trails clear of snow anyway. Mid-July through early September is peak season, with wildflowers filling the meadows below Isabelle and long, mostly dry mornings. Late September into early October trades flowers for golden light and thinner crowds, though Lake Isabelle will be low by then.

Whenever you go, treat the weather as the boss. Afternoon thunderstorms build fast over the divide in summer, and you do not want to be standing on Pawnee Pass when they do. Aim to be off the high ground by noon. Mornings up here start cold even in July, so pack layers no matter what the Boulder forecast says. If you're planning a whole week of hikes like this, our best hikes near Boulder list pairs well with a Brainard day.

Long Lake and the Indian Peaks reflected in still morning water near the trailhead
Calm mornings turn Long Lake into a mirror for the Indian Peaks, one of the easiest big views in the range.

What to Pack {#what-to-pack}

You're starting above 10,000 feet and can climb well past 12,000, so pack for real mountain weather even on a bluebird morning.

A comfortable daypack. Enough room for layers, water, and lunch. See our best hiking daypacks roundup, or browse daypacks on Amazon.
A rain shell. Non-negotiable for afternoon storms. Grab a packable rain jacket.
An insulating layer. A light down or synthetic jacket for cold starts and windy passes.
Trekking poles. Your knees will thank you on the Pawnee descent. Here are trekking poles.
Water and a way to treat more. Carry two liters and a water filter for longer days.
Sun and bug protection. The high sun is fierce, and mosquitoes near the lakes are brutal in early summer, so bring sunscreen and bug spray.

Frequently Asked Questions {#faq}

Do you need a reservation for the Long Lake Trailhead?

Yes. From June 12 through October 1, 2026, every vehicle entering the Brainard Lake Recreation Area needs a timed-entry reservation from Recreation.gov, which costs $16 per vehicle. You can also walk or bike in from the Gateway Trailhead without a reservation.

How long is the hike from Long Lake to Lake Isabelle?

Lake Isabelle is about 4.5 miles round trip from the Long Lake Trailhead, with roughly 600 feet of elevation gain. It's a moderate hike that most fit walkers finish in three to four hours, longer if you linger for photos or lunch at the lake.

How hard is the Long Lake Trailhead to Pawnee Pass?

Pawnee Pass is a hard hike: about 9.5 miles round trip with around 2,100 feet of gain, topping out at 12,550 feet on the Continental Divide. The altitude and afternoon storm risk make it a serious day, so start at first light and turn around if the sky darkens.

When does the Long Lake Trailhead parking lot fill up?

On summer weekends the small Long Lake lot often fills by 7 a.m., sometimes earlier. Arrive at first light, choose a weekday, or use the larger Brainard Lake day-use lots below as backup parking.

Can you see moose at the Long Lake Trailhead?

Often, yes. The willows along the South St. Vrain valley between Long Lake and Lake Isabelle are prime moose habitat. Keep at least 50 feet away, give extra room to any cow with a calf, and never approach one for a photo.

Plan the Trip

The Long Lake Trailhead gives you four hikes for one reservation, from a fifteen-minute lakeside stroll to a 12,550-foot pass. Book your Recreation.gov slot early, set your alarm, and pack for weather that changes by the hour. When you're ready to keep exploring the range, our best hikes in Indian Peaks Wilderness guide maps out where to go next.