Question: Where is the United Kingdom's largest indoor water park located?

<P0-S0> Mt. Olympus Water and Theme Park is a theme park and water park complex in Wisconsin Dells, Wisconsin. <P0-S1>  Mt. Olympus consists of four areas of the park: Zeus' Playground (outdoor theme park), Neptune's Water Kingdom (outdoor waterpark), The Parthenon (indoor theme park), and Medusa's indoor water park. <P0-S2>  In 2010 and 2011, the park purchased several smaller nearby independent motels and hotels and renamed them, painting them blue and white to fit the Greek theme for the main hotel. <P0-S3>  Many other area hotels and motels offer free or reduced-priced tickets. <SEP> <P1-S0>  It opened in 1986 on the site of the former South Shore Open Air Baths as a joint public/private partnership. <P1-S1> Sandcastle Waterpark is an indoor waterpark in an 84-degree tropical climate located at South Beach in Blackpool, Lancashire, England. <P1-S2>  Sandcastle Waterpark has more than 18 slides and attractions. <SEP> <P2-S0> Ray's Splash Planet (often referred to as Ray's) is a Mecklenburg County, North Carolina funded water park located in Charlotte, North Carolina, United States. <P2-S1>  The aquatic facility is operated by the Mecklenburg County Park and Recreation department. <P2-S2>  Ray's Splash Planet is considered one of the largest indoor water parks in both of the Carolinas and is the largest water park in Charlotte, North Carolina, with over 29,000 square feet of space and using over 117,000 gallons of water at 87 degrees. <P2-S3>  The water is cleaned and sanitized through the use of chlorine, filtration and an ultraviolet germicidal irradiation system. <P2-S4>  There are multiple attractions including the Blue Comet, a three story figure 8 slide, and other family friendly attractions like the Orbiter, Saturation Station, the Vortex, Meteor Showers, Moon Beach and the Sea of Tranquility. <P2-S5>  The water park also features a fitness center and gymnasium shared with the Irwin Academic Center, an educational center of the Charlotte-Mecklenburg Schools system. <P2-S6>  The first floor of the facility includes the pool area, locker rooms, birthday party classrooms and concessions stand. <P2-S7>  The second story includes the fitness center with an aerobics/dance studio. <P2-S8>  Access to the indoor gymnasium is also located on the second floor. <P2-S9>  Ray's Splash Planet is located on North Sycamore Street near Johnson & Wales University and is just off Interstate 77 in North Carolina in the Third Ward section of Uptown Charlotte. <P2-S10>  The water park opened on October 15, 2002 with help from Mecklenburg County Park and Recreation's partnership with Charlotte-Mecklenburg Schools. <P2-S11>  Major competitors are Carowinds in Charlotte, North Carolina, Great Wolf Lodge in Concord, North Carolina and Wet 'n Wild Emerald Pointe in Greensboro, North Carolina. <SEP> <P3-S0> Wet N Wild is an indoor water park situated in North Shields, Tyne and Wear, England. <P3-S1>  It was the United Kingdom's largest indoor water park when opened in 1993, a title subsequently claimed by Sandcastle Waterpark. <P3-S2>  The park is situated in the Royal Quays complex, and features numerous slides, a wave machine, and rapids. <P3-S3>  It was confirmed Wet N Wild would reopen following a takeover by Moirai Capital Investments;