Where: Colorado

Why: Here you can take a swing at Rocky Mountain’s “Grand Slam,” a two-day trek across the Mummy Range. The two-day journey crosses 18 miles of alpine tundra, tagging nine 11,500-plus-foot summits along the way. Get an elevation head start at Chapin Creek (10,640 feet), and camp at Lawn Lake to prep for day two. Remember to follow hardened surfaces and trails left by bighorn sheep or fellow summit-baggers, being careful not to crush the fragile tundra plant life. More Info

Runner-up: Olympic National Park, Washington
For a longer stay beneath the open sky, try the two-week, 93-mile Wonderland Trail that loops beneath Mt.Rainier’s summit, taking in conifer forests, alpine ridges, rushing rivers and rolling wildflower meadows. More Info