The park’s alpine terrain includes the major peaks of the 40-mile-long Teton Range as well as most of the northern sections of the valley known as Jackson Hole. A dozen small glaciers, the Snake River, streams and numerous crystalline lakes provide a welcome reprieve from the heat of summer. Although Grand Teton is only 10 miles south of Yellowstone National Park, it’s generally less crowded. Campgrounds, as well as several excellent lodging facilities ranging from cabins to resort hotels, are located inside the park.
The park comprises 21 islands — the “Jewels of Lake Superior” — and the northern tip of Wisconsin. Lake Superior is the cleanest of the Great Lakes, and you can enjoy scuba diving amid old shipwrecks. The islands’ pristine beaches, protected bays and public docks make for outstanding boating, fishing and kayaking. Twelve of the islands have maintained trails — more than 50 miles total — leading to historic lighthouses, abandoned quarries, old farm sites, scenic overlooks, beaches and campsites.
5. Zion National Park, Utah
Hot summer weather is perfect for hiking the Virgin River at the base of the park’s upper canyon, otherwise known as “The Narrows.” The trail is literally the river — trekkers walk, wade and swim through the 16-mile route, penned in on both sides by 2,000-foot vertical sandstone walls. The hike is strenuous (trekking poles or a walking stick are essential to negotiate the slippery rocks and moving current), but well worth the effort for the unique experience and awe-inspiring scenery. Check the schedule of performances at the O.C. Tanner Amphitheater, located just outside the south entry gate in Springdale.
6. Mammoth Cave National Park, Kentucky
The cool, dark passages of the world’s longest cave system (400 miles have been explored so far) offer a great reprieve from the summer heat. Rangers lead more than a dozen different tours, including the Wild Cave Tour that gets visitors off the beaten track to climb, crawl and slither through more remote sections of cave. Aboveground, enjoy boating, canoeing, kayaking, fishing and riverside camping along the more than 30 miles of the Green and Nolin rivers that run through the park.