Mount Whitney at 14,505 feet, is the tallest in the Continental U.S. It is located in the John Muir Wilderness and Sequoia National Park in the eastern Sierra Nevada Mountains. Backpackers and hikers should stick to the western approach up the 22-mile roundtrip Mt. Whitney Trail. It can be done in one day, but most people complete it in two to three for a more comfortable, acclimatized ascent. There are no glaciers or tricky scrambles, so you won't need technical skills. You can even climb to the top in sneakers.