World's Largest Indoor Water Park is in Japan

Ocean Dome is listed in the Guinness Book of World Records as the world's largest indoor water park, measuring 300 meters in length, 100 meters in width. And the temperature is 30 degrees Celsius year-round.

Located in the Sheraton Seagaia Resort, a large resort complex in Miyazaki, Japan, the Ocean Dome features a wave pool (surges a 6-10 foot waves) and holds 13,500 tons of water, has a depth of 3.5 metres (about 10 feet) along the 70-meter-long back wall.

There are quite a few differences between the Ocean Dome and the ocean, among them the heated indoor pool, the kids’ pool, the floating pool, and the three fast and water slides.

Pretty crazy ass stuff. More pictures here.