Premise: World Waterpark is a water park located at West Edmonton Mall in Edmonton, Alberta, Canada. Opened to the public in 1986, it is the world's second-largest indoor water park after the Tropical Islands Resort in Germany. It has a maximum capacity of 5000 guests, an average air temperature of 31 °C , and contains the world's largest indoor wave pool with a capacity of 12.3 million litres.
Hypothesis: Tropical Islands Resort is the largest indoor water park.