Phantom Ranch (Grand Canyon, Arizona)
Reached by foot, mule, or river, this mostly dorm-style retreat is the only lodging below the Canyon's rim. Trek to Roaring Springs waterfalls, tackle Class III rapids on the Colorado, or hike to Yaki Point for the best sunset in the entire Canyon.
More information: Reservations are available 13 months in advance and are not available online. [from $44; grandcanyonlodges.com].