Mount Rainier National Park in Washington is a trail runner’s paradise. The Skyline Trail is a favorite because it’s just 5.5 miles long but has a 1,400-foot elevation gain, which means you might need to hike parts of the trail unless you’re in terrific shape. You’ll cruise by wildflower meadows galore and get plenty of views of the Tatoosh Range and other Cascade peaks — including Rainier, of course. Another interesting trail-running option is running sections of the 93-mile Wonderland Trail, which travels around the snow-capped volcano and passes by plenty of backcountry camps. The almost 20,000 feet of elevation change on this trail over its entirety makes this a truly tough run.