Boulder has no shortage of hikes featuring incredible destinations, geological curiosities, and breathtaking views. From sweeping summits to rambling rivers, our local trails can take you to some pretty spectacular spots. But few trailside attractions are quite as exhilarating as a glacier.
Colorado is home to 14 named glaciers and many are accessible from Boulder. Arapaho Glacier, located near the tiny town of Eldora, is the largest in the state. In the past, this mass of snow and ice provided Boulder County with much of its drinking water. Multiple well-trodden trails lead to the Arapaho Glacier overlook.
A few miles north of Arapaho Glacier, lies Isabelle Glacier. Though smaller than Arapaho, it’s still a sizeable glacier nestled in a cirque of pristine alpine peaks. Isabelle serves as the headwaters for a multitude of lakes, as well as the South Saint Vrain Creek. The trek to this glacier is a little bit trickier and the window for optimal conditions is a little bit smaller. As a result, Isabelle Glacier offers a more “off the beaten path” experience, and yet it’s still less than an hour from Boulder.
Isabelle Glacier is most easily accessed out of the bustling Brainard Lake Recreation Area. As experienced locals will tell you, there is nothing “off the beaten path” about this trailhead or the trails in its immediate vicinity. Throngs of summer visitors descend upon this region to enjoy more mellow hikes like Long Lake and Lake Isabelle. But beyond these popular spots, the crowds thin dramatically, along with the air, and you’ll have plenty of room to breathe.
The 8.8-mile round trip hike to Isabelle Glacier is strenuous but rife with rewards. Winter conditions linger in this area for much of the year. Brainard Lake Road is closed from mid-October to mid-June (exact dates vary from year-to-year). Interior access roads may be closed for even longer. Late July to early September is the best times of year to attempt this hike.
Before heading out, be sure to check for both trail and road conditions in Brainard Lake Recreation Area. Foot traction such as microspikes may be desired, even in summer months. Start your hike early and plan to be below tree line by 1:00 pm to avoid afternoon thunderstorms.
Get there
From Boulder, head west on CO-119 to Nederland. At the rotary, take CO-72 W toward Ward. Turn left (west) onto Brainard Lake Road. Continue to the entrance pay station. There’s an $11 fee to enter Brainard Lake Recreation Area.
From the pay station, follow signs to Long Lake Trailhead. (If Long Lake Trailhead is full, you can return the way you came and park at the larger lot by Brainard Lake. This adds about 1.2 miles to your hike.)
Hike it
From the trailhead, begin hiking west on the well-marked trail following the north shore of Long Lake.
You’ll pass through two junctions for the Jean Lunning Trail, which takes hikers to the other side of Long Lake. Remain on the trail heading toward Lake Isabelle. Keep your eyes open as moose are very active here.
At 1.8 miles, the trail begins to switchback and steepen. At 2.1 miles, you’ll reach the eastern end of Lake Isabelle.
For many hikers, this is the end of the line. For you, it’s a great place to rest, have a snack, take a few photos, and get ready for the hard part.
From here, the trail becomes more difficult to follow as it rises up through the glacial valley. Stay to the right and follow signage for Isabelle Glacier. At 2.6 miles, you’ll leave Lake Isabelle behind. From this point on, a few scattered cairns and good common sense will be your guide.
You’ll gain 3 distinct ridges or benches as you continue your ascent to the glacier. (On your way back, you can save some time and inject a little fun into your hike by glissading or butt sledding down them.) At 3.2 miles, the trail turns to the south while taking you through a marshy maze of trickling snowmelt, streams, and ponds. Don’t forget to turn around occasionally for breathtaking views of Lake Isabelle and Long Lake, now far below to the east.
At 3.75 miles, you’ll reach the edge of Isabelle’s tarn (a crystal blue lake at the bottom of the glacier).
It’s a dramatic and welcome sight after some stealthy route finding. The glacier is in front of you (along with Navajo, Apache, and Shoshoni Peaks) and you’re welcome to stop here, or continue the final 0.5-mile scramble to the very top. The unmarked but intuitive route hugs the north side of the tarn before leveling out and bending to the west.
Be mindful of this fragile landscape while you explore. The glacier itself is ever changing and unstable by nature, while the delicate tundra surrounding it is home to countless plant and animal life. Once you’ve had your fill of this special place, retrace your steps and return to the trailhead as you came. The hike to Isabelle Glacier is 8.75 miles round trip with about 1,500 feet of elevation gain.
And BOOM, you just hiked a glacier. Happy trails, Boulderites!
Photo credit: Alli Fronzaglia for YourBoulder.com — all rights reserved
