February 28, 2008 Looking to beat the heat this summer by installing your own swimming pool? We thought we would give you a taste of what you almost certainly can't have when designing your dream backyard aquatic paradise. Firstly, there's the world's largest pool with an area equivalent to an incredible 6,000 standard-size 26 ft long domestic pools located at the San Alfonso Del Mar resort in Chile, and, going to the other extreme, there's Belgium's amazing 100 foot deep, 660,000 gallon (and heated!) Nemo33 dive pool.

The pool at the San Alfonso Del Mar resort in Chile, South America is absolutely enormous. In fact, it is so massive the Guinness World Records Ltd has officially named it the world’s largest seawater swimming pool. It is 3,324 ft long (1013 meters) with a colossal area of 19.77 acres (8 ha) and contains over 66,000,000 gallons of water. (250,000 cubic meters) That’s an area equivalent to an amazing 6,000 standard-size 26 ft long (8-meter) domestic pools!

The “lagoon” at the San Alfonso Del Mar resort has clear blue water pools which are transparent to a depth of up to 115 feet (35 meters) and in summer the temperature of the water is a balmy 79ºF (26ºC), that’s 48ºF (9ºC ) warmer than the sea. The lagoon also protects holiday-makers from the rough waves and notorious currents along the coast.

In order to fill this incredible lagoon, the Crystal Lagoons Corporation developed innovative technology to harvest, filter and permanently re-circulate sea-water. The computer-controlled suction and filtration system keeps the seawater in permanent rotation. It takes in the ocean water, circulates it through the system and then pumps it out the other end.

Biochemist, Chilean businessman and founder of Crystal Lagoons, Fernando Fischmann, said advanced engineering meant his company could build "an impressive artificial paradise" even in inhospitable areas.

"As long as we have access to unlimited seawater, we can make it work, and it causes no damage to the ocean." And you could be forgiven for thinking you are swimming alone in the ocean…but then a kayak passes you and it becomes a little surreal. Yes, you can sail small boats or paddle your canoe if you feel the need, this pool is big enough for everyone.

The resort project took over five years to build and cost nearly US $1.9 billion and carries an annual maintenance bill of nearly US$4 million. If you’re a lucky guest you could imagine you’re on a desert island with private white-sand beaches and palm trees, an indoor warm-water beach, heated sand, waterfalls and water-jet massages.

If you prefer to stay indoors, how about the world’s deepest recreational diving pool? Situated in Belgium, the Nemo 33 pool has a depth of just over 100 ft (approx 33 m). The pool was designed by a Belgian diving expert, John Beernaerts and is used for recreation, scuba diving practice and instruction and by film-makers and scientists.

It contains approx. 660,500 gallons (2,500,000 liters) of spring water maintained at a temperature of 86°F (30°C) and has visibility up to 108 ft (33 m). The computer-controlled filtration system ensures there is little or no chlorine smell and fourteen windows allow visitors to view all the underwater action.

The pool has a number of underwater caves at 33 feet (10 meters) and two flat-bottomed areas at 16.5 and 33 feet (approx. 5 and 10 meters) as well as the afore-mentioned large circular pit at 108 feet (33 meters).

Three pressurized rooms at -30 and -23 feet (-9 and-7 meters) with constantly renewed air gives divers and their instructors more time at the bottom, free Aqualung diving gear is available at the side of the pool and Nemo 33 is in partnership with the Professional Association of Diving Instructors (PADI). The pool has varying depths so it’s suitable for experienced and inexperienced divers and you can fill your air tank by the side of the pool. Racing your “buddy” to the bottom of the pool just got a whole lot more interesting.

If these extreme examples have wet your appetite for exotic pools, check out the listing at Oobject or let us know if you've spotted even more outlandish aquatic facilities in your travels.

View gallery - 6 images