The ocean's ultra-Maytag effect churns away at fresh lava, which turns a glistening black when it cools, into sand particles in a matter of years on the Puna coast of the Big Island of Hawaii. Pictured here is Kehena Black Sand Beach, a.k.a. 19-Mile Beach since it resides at that mile marker on the highway. A short, hands-on trail leads down from guardrail parking, made more of a scramble one day in 1955 when volcano goddess Pele sneezed and the earth fell five feet in a jiffy flat at the shoreline—you can see the demarkation clearly where a stairway was severed.
BTW: People like no go naked here, even though nudity is not allowed on any Hawaiian beaches, which are all public places.