The Glass beach in Fort Bragg, California. For over 60 years it was a dumping area for glass and other litter, which became rounded with the waves effect. After some time the rubbish was removed and only the small glass pieces remained. If you'd like to see it, hurry up! There's plenty of tourists that are taking home the glass sand as souvenirs!
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Rosario Fiore - flickr (CC BY-ND 2.0)