Treehotel
This series of eight glass cubes and other unusual structures suspended among the pine trees of a Swedish forest is not art installation—it's a hotel. Family owned and operated, the eco-friendly, low-impact property has been welcoming adventurous guests since 2010. Constructed with local materials, the eight "tree" rooms are set at various heights above the ground (ranging from 13 to 33 feet), and each one is different in shape and furnishings. Choose from a mirror cube, a bird’s nest, a UFO, or other uniquely designed accommodation and enjoy the feeling of unwinding in a natural setting. Since resort activities and amenities are limited—only two of the tree rooms have en suite showers—most guests come to simply enjoy the view, the tranquility, and the unique overnight experience. There's also a guesthouse with regular rooms if you prefer to keep your feet on the ground; other facilities include a restaurant, a bar, and a sauna.