World's largest outdoor poolMay 22, 2012 at 11:49 PMLink CopiedRead full article1 / 17World's largest outdoor pool Photo courtesy of Crystal Lagoons Corp. The Crystal Lagoon, located at the San Alfonso del Mar resort in Algarrobo, Chile, is the world's largest outdoor pool, stretching more than half of a mile and filled with 66 million gallons of water. View comments