The largest of the Canary Islands, Tenerife is a wellspring of natural and archeological treasures. Whether upscale travelers are visiting the island to hike its ancient forests and volcanic countryside, meander through its Spanish colonial villages, or simply gaze at the sea -- keeping an eye out for the whales and dolphins that are so often seen off of Tenerife's coast -- they might find themselves most comfortable and content at these 10 luxury hotels, ranked by Oyster's hotel investigators to be the best of the best.