There is a Atlantis Sanya. Also there are a lot water sport activities.Certainly they are lots of luxury resorts and recreational facilities, but no big theme parks. The supply is lower than demand, and the beachfront is overcrowded. After all, this is a one billion strong market with spending power. All Chinese go to Sanya for summer/romantic vacation. There is enough demand to turn the whole island into one big theme park.
There's so much opportunity for SeaWorld Universal Studios Disney World etc to move in and satisfy the Chinese consumer. And 欢乐谷.