Grinnell Lake

Overview

Grinnell Lake is the Many Glacier showstopper: an opaque turquoise tarn pooled beneath Angel Wing and Mount Grinnell, with threads of waterfalls cascading into a steep-walled basin. It’s a classic day hike that trades big mountain drama for relatively easy mileage, so it’s popular—and for good reason.

Getting There

Most hikers start near Many Glacier Hotel and follow trails past Swiftcurrent and Lake Josephine. It’s roughly 6.8 miles round trip on foot, or you can combine hiking with the seasonal boat shuttles across Swiftcurrent and Josephine to knock off some early miles. Expect a well-used path with short boardwalks and at least one small swinging bridge along the way.

What You’ll See

The color is the headline: rock flour from upstream glacial melt turns the lake an unreal blue-green. The cirque rises straight from the shore, waterfalls pour off ledges, and the whole scene begs for photos. On sunny days the water glows; climb higher on nearby trail sections if you want the best overall views of the basin.

Wildlife

This corridor is rich habitat. Sightings reported in the area include bears, moose, mountain goats, bighorn sheep, and plenty of birdlife. Aim for early or late in the day for your best chance, carry bear spray, and make noise in brushy stretches.

Amenities and Logistics

There’s no road access and no parking at the lake—this is a hike-in destination. Services are sparse; a basic pit toilet sits just before you reach the lakeshore. Otherwise, plan to be self-sufficient with water, snacks, and layers.

Best Time to Visit

• Season: Peak summer brings the biggest crowds. Shoulder season can be quieter, but early season snow and ice may linger on the trail.
• Time of day: Arrive early to find parking at Many Glacier and enjoy calmer lakes. For photography, sunny conditions make the turquoise really pop.
• Day of week: Weekdays are generally less busy than weekends.

History & Geology

Named for conservationist George Bird Grinnell, the lake fills a glacier-carved basin. Its vivid color comes from fine rock particles—glacial silt—washed down from Grinnell Glacier into Upper Grinnell Lake and then into Grinnell Lake.

Trail Conditions & Safety

This is a popular, comparatively gentle outing, but it’s still alpine country. Snow and ice can persist early; traction can help. Bears and moose are around, so keep your distance, hike in groups, and carry bear spray. Dogs aren’t allowed on the trail.