Lava from the Kilauea Volcano obliterated the world-famous Kalapana Black Sand beach in the 1990s, but there are others to explore in Puna and Kau (KAH-oo), near Hawaii Volcanoes National Park. Fringed with coconut palms, Punaluu offers the choicest setting for a swim in impossibly blue water. Also a popular nesting spot for Hawaii's green sea turtles.