Brian Head Resort: At 11,307 feet, there may not be a lot of oxygen, but the air is pure and clear, and the biking is great -- especially when you can ride a chairlift up and bike down. There are trails everywhere, each with more magnificent scenery than the last.
Dave's Hollow Trail: Situated just outside the entrance to Bryce Canyon National Park, this trail heads off into the national forest. The double track takes you through sun-dappled glades surrounded by tall ponderosa pines and spruce trees, all the way to fishing and camping at Tropic Reservoir.
Moab Slickrock Bike Trail: A rite of passage for serious mountain bikers, this challenging yet rewarding trail takes 4 to 5 hours to complete. You'll enjoy breathtaking views of the Colorado River far below, the La Sal Mountains towering above, and the red sandstone formations of Arches National Park in the distance.