Rocky Mountain National Park
Rugged alpine scenery and abundant wildlife make this International Biosphere Reserve justifiably popular. A third of the park lies above timberline, and 60 of its summits surpass 12,000 feet. Elk, bighorn sheep, and summer wildflowers enliven the landscape. For a scenic smorgasbord of deep forests, emerald lakes, and spectacular pinnacles, follow the Glacier Gorge Trail. Avoid the summer season, when permits are scarce.
Contact: Rocky Mountain National Park, (970) 586-1242; www.nps.gov/romo.
It's hard to find a backpacking spot that's better than this 488,000-acre jewel in the crown of Colorado's craggy San Juan Range. The average elevation is above 10,000 feet, and summer wildflower displays are magnificent enough to convince atheists of a higher power. Hike the Vallecito Creek Trail 17 miles to Hunchback Pass on the Continental Divide. Spurs lead east and west to paradise.
Contact: Rio Grande National Forest, (719) 852-5941; www.fs.fed.us/r2/riogrande.
Winding 471 miles from Denver to Durango, the Colorado Trail offers many Rocky Mountain highs. The least crowded section may be the 53 miles between CO 114 and CO 149, where the La Garita Wilderness offers spectacular alpine rambling.
Contact: Colorado Trail Foundation, (303) 384-3729, ext. 113; www.coloradotrail.org.