Virgin Valley Warm Springs (Sheldon NWR campground)

Way up in the remote Sheldon National Wildlife Refuge near the Oregon line, in a valley known for opal mining, the refuge campground pipes warm spring water into a pool. There's drinking water, pit toilets and a rustic shower house, which counts as comfort out here. It's free, first-come first-served, open all year, and you can stay up to 14 days in any 30. Turn onto Virgin Valley Road off NV 140; the campground is 1.5 miles from refuge headquarters. They don't publish a water temperature, and it's billed as warm, so think bath rather than hot tub.