The 20 Most Challenging Hikes in America, Ranked

16. Paintbrush Canyon & String Lake Loop – Grand Teton National Park, Wyoming

Difficulty: Class 2

A true backcountry adventure, the Paintbrush Canyon & String Lake Loop spans 20.6 miles through the stunning landscapes of Grand Teton National Park. With over 4,000 feet of elevation gain, this hike is not for the faint of heart, but those who tackle it are rewarded with alpine lakes, sandy beaches, and breathtaking mountain views.

The trail leads to the tranquil Lake Solitude, offering unparalleled views of the Tetons and excellent wildlife-spotting opportunities. Best hiked between March and September, this route is popular for camping and birding. To preserve the park’s ecosystem, dogs are not permitted on the trail.