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San Alfonso Del Mar

Where: Chile



The largest swimming pool in the world is more than 3000 feet long, with a deep end that descends 115 feet. Sitting seaside at a resort in Chile, the pool required nearly five years to build and cost $1.6 billion. It has an annual maintenance fee of $3.2 million. Containing more than 66 million gallons of water, it dwarfs the second biggest pool in the world (the Orthlieb in Morocco with a mere 9.5 million gallons). The pool keeps a constant flow of fresh seawater into the pool and old water back out to the sea, using a filtration system to desalinate the seawater before it goes into the pool and clean the pool water before it goes back to the ocean.