GREAT AMERICAN VACATION
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If you aren't used to it, high altitude can catch you off guard. Drink plenty of water to help stave off the effects of altitude sickness—dizziness, shortness of breath, headache, and nausea. Slather on the sunscreen—it's easy to get sunburned up here. And in summer an early morning start is best, as afternoon thunderstorms are frequent and a danger above the tree line.
Booth Lake. This is one of Vail's most popular hikes, so get on the trail early or pick a weekday during the summer high season. This is a sustained 6-mile one-way climb from 8,400 feet to Booth Lake at 11,500 feet, right above the tree line. Fit hikers can do this in about seven hours. En route, hikers can cool off at the 60-foot Booth Creek Falls; at only 2 miles in, this is also a great spot to turn around if you're feeling winded (this should take about two to three hours round-trip, and is a great option for an easier hike). The reward for pushing on is a nice view of Booth Lake cradled among the alpine tundra. Trailhead: Take Exit 180 from I–70 to end of Booth Falls Rd., Vail, CO, 81658.
Eagle's Loop. This trail starts from atop the Eagle Bahn Gondola at 10,350 feet, but it's a mellow, 1-mile stroll along the mountaintop ridge with panoramic views of the Mount of the Holy Cross. Allow about half an hour. One-day lift ticket for the 14-minute gondola ride is $26 for adults. Trailhead: Top of Eagle Bahn Gondola, Vail, CO, 81657.
Paragon Guides. In summer, this backcountry adventure company offers rock climbing, mountain biking, and day and overnight llama treks in and around Vail Valley. In winter the company runs daylong ski trips through the backcountry, and three- to six-day trips along the 10th Mountain Division Hut System. Vail, CO, 81658. 970/926–5299. www.paragonguides.com.