Head to the mountain-biking Mecca of Crested Butte. The Fat Tire Festival convenes in June, but if you're not there for that, try riding Pearl Pass into Aspen, where you'll get views, switchbacks, and waterfalls.
Take your bike up a chairlift! Many of the ski resorts operate their lifts during the summer, adapted with bike attachments. Catch a ride up, then coast down on your knobby tires through the forests of pine.
It's no easy ride, but the Vail Pass to Redcliffe bike route offers great views to soothe your burning muscles. You'll see the Mount Holy Cross overlook and climb past 11,000 feet.
Check out the Government Trail, which winds from Aspen to Snowmass. You should have your biking skills perfected in order to tackle the switchbacks near the beginning. Your reward? Pleasantly rolling terrain, scenery, and glorious Rocky Mountain wildlife.
In Summit County, try the Glenwood Canyon Trail, a 16-mile route that follows the Colorado River through dramatic Glenwood Canyon. Unfortunately, you'll have to tune out the traffic from I-70.
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