Yap, Micronesia

You may have never heard of this little island, but ask any true scuba diver about Yap and he'll surely respond approvingly. The island (located only 6,000 miles from Los Angeles; an hour's flight from Guam) is known for its pristine water and abundant marine life. In fact, ecologists, explorers and general nature enthusiasts visit because it's the best location to spot the mysterious manta ray.

Best visited during the December through April dry season, this spot's simple purity makes it unique; no resort hotel or loud pub can be seen on its beaches. Instead, all you get is some of the world's best diving opportunities, replete with underwater caverns, and shark and sea turtle sightings, in addition to the numerous rays.