Located in Montana's Glacier National Park, Hicks says this route covers about 7.6 miles out and back. The trail’s first two miles are mostly flat but past that point runners can expect a gradual incline up to the end. “From bighorn sheep to bears, lots of wildlife sightings are possible in addition to the gorgeous turquoise blue ice of the glacier itself,” says Hicks. Oh yeah, and be sure to follow safety instructions. Hicks says this hike travels through grizzly-bear habitat.