2 Best Sights in Longs Peak, Rocky Mountain National Park

Nestled in the shadow of Longs Peak and Mt. Meeker, Chasm Lake offers one of Colorado's most impressive backdrops, which also means you can expect to encounter plenty of other hikers on the way. The 4.2-mile Chasm Lake Trail, reached via the Longs Peak Trail, has a 2,360-foot elevation gain. Just before the lake, you'll need to climb a small rock ledge, which can be a bit of a challenge for the less sure-footed; follow the cairns for the most straightforward route. Once atop the ledge, you'll catch your first memorable view of the lake. Difficult.

Climbing this 14,259-foot mountain (one of 53 "Fourteeners" in Colorado) is an ambitious goal for almost anyone—but only those who are very fit and acclimated to the altitude should attempt it. The 16-mile round-trip climb requires a predawn start (3 am is ideal), so that you're off the summit before the typical summer afternoon thunderstorm hits. Also, the last 2 miles or so of the trail are very exposed—you have to traverse narrow ledges with vertigo-inducing drop-offs. That said, summiting Longs can be one of the most rewarding experiences you'll ever have. The Keyhole route is the most popular means of ascent, and the number of people going up it on a summer day can be astounding, given the rigors of the climb. Though just as scenic, the Loft route, between Longs and Mt. Meeker from Chasm Lake, is less crowded but not as clearly marked and therefore more difficult to navigate. Difficult.