San Alfonso Del Mar Pool And Resort, Algarrobo, Chile

Pool and resort
San Alfonso's pool is 1 kilometre (3/5 mile) long. The pool covers an area of 7.7 hectares (19 acres) that holds 250 million liters (66 million gallons) of seawater. The pool, developed by Chilean company Crystal Lagoons, uses water pumped, filtered, and treated from the Pacific Ocean to supply to the pool.