Now that’s a Pool! The World’s Largest Pool

September 2, 2014

San Alfonso del Mar 1
Crystal Lagoons

Want to take a dip in the most impressive pool in the world?  If so, do I have a pool for you.  It’s so large you can scuba dive in it, sail a boat, heck, you could get lost in it.  It’s the world’s largest pool, and it’s at the San Alfonso del Mar Resort in Chile.

The massive pool at the San Alfonso del Mar Resort seems strange at first glance.  It sits directly beside the ocean and a sandy beach.  Why build a pool when you could just as easily walk over to the beach?  For one, this area of ocean is cold, and it’s also dangerous.  Swimming is even prohibited in the area.  So the resort had a problem–what can attract tourists to an area next to the beach where they’re not even allowed in the ocean?  The technology wasn’t there to make a pool this size, or what is more commonly called a lagoon.  After many years of testing, a company called Crystal Lagoons developed the technology to make a crystal clear lagoon in an inhospitable environment.

Proyecto San Alfonso del Mar
Crystal Lagoons

The pool is huge, very huge.  It covers almost 20 acres and holds an astounding 66 million gallons of water.  That is the equivalent of 100 Olympic-sized swimming pools that hold 660,000 gallons each.  It’s also long, measuring in at 3,324 feet.  To put this in perspective that is about 11 football fields.  Now that makes for one long lap.  If the length and amount of water this thing hold is impressive, the depth is also amazing.  It holds the Guinness World Record for being the deepest pool at 115 feet.  Common recreation diving, for the most part, usually takes place from 60-100 feet in depth.


One thing that the pool does remarkably well, given its location to the ocean, is its regulation at a consistent temperature.  While the ocean just beyond its walls reads a crisp 59 degrees, the pool regularly hovers at around 78 degrees.  That makes the option of swimming much more palatable, but there aren’t really any other options since swimming is prohibited in the ocean next door.

The Crystal Lagoons Corporation, which designed, built, and maintains the lagoon, uses the ocean next to it to feed the salt water lagoon.  It relies on a sophisticated series of filtration systems to clean the water after it is sucked in by using a computer controlled system.  The system then returns the water to the sea.  It is a efficient system that wouldn’t have been possible in previous years with previous technology.  The costs would have been too high.

800px San Alfonso del Mar 2

There is plenty to do on the huge lagoon.  Go scuba diving, paddle a kayak, or even sail in a sailboat.  The lagoon is large enough to accommodate almost anything.  All of this does come at a price.  The price tag for maintaining the pool is over $3 million dollars a year, but that is a drop in the bucket with the $1.5 billion it took to construct it.  Still, the maintenance cost of a pool this size with the amount of water it has is actually quite low.  You can see from the aerial picture below the true magnitude of the lagoon at the San Alfonso del Mar Resort.  Who wouldn’t want to dip a toe into that?

sanaloysoresort2Thanks for reading.  Now I know you want to book a trip to check this sucker out.  Am I right? 

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About the author 

Daniel Ganninger - The writer, editor, and chief lackey of Knowledge Stew, the author of the Knowledge Stew line of trivia books, and editor of Fact World and the Knowledge Stew sister site on Medium, our ad-free subscription sites (you can find out how to join below). I hope you find things here to annoy those around you with your new found knowledge.

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