Where is the largest swimming pool in the world, and how big is it?

The largest swimming pool in the world is the sea water Orthlieb pool in Casablanca, Morocco. It is a saltwater pool and is 480m (1575 ft) long and 75m (246 ft) wide with an area of 3.6 hectares (36,000 sq m).
http://www.blurtit.com/q237628.html

The pool is 480 meters or 1,574 feet long and 75 meters or 246 feet wide. The Orthlieb Pool is filled with sea water and covers a soggy 8.9 acres.

Also this, in Garden City, Kansas: The 'Big Dipper' as it was called in 1922 when it was first built, is a very large pool. When all the adjectives are added, it is the 'largest outdoor, concrete, free, municipal pool in the world'. The pool measures 220 feet by 330 feet, roughly the size of a football field. As a promotion for a post card many years ago, a motor boat was placed on the water and pulled a water skier around the pool! Large as it is, it is not the world's largest pool. There are others that are larger. We are the world's largest free swimming pool in the world. The pool holds approximately 2.6 million gallons of water.
https://www.travelks.com/listing/big-pool/2725/

The largest swimming pool in the world certified by Guinness is San Alfonso del Mar pool in Algarrobo, Chile.
http://www.sanalfonso.cl/

Already drawing the crowds in the South American resort of San Alfonso del Mar in Chile, this artificial lagoon and swimming pool is eight hectares in size and contains an incredible 250,000 cubic metres of water. Acknowledged by Guinness World Records as being the world’s largest swimming pool, the lagoon trounces all other record holders in the category, including the Orthlieb pool in Casablanca, Morocco, itself a huge 150 metres by 100 metres – the San Alfonso pool is ten times this size, measuring 1km in length. The revolutionary clear water artificial lagoons, transparent to a depth of 35 metres and unprecedented in design and construction methods, are the brainchild of Crystal Lagoons founder, biochemist and Chilean businessman Fernando Fischmann. Equivalent in size to an incredible 6,000 standard domestic pools, details of its technology are to be unveiled for the first time at Cityscape Dubai later this month.

http://www.wonderfulinfo.com/amazing/unbelv/largestpool/