Yalong Bay translates as Asia Dragon Bay, and is a 7.5-kilometer beach area. A lot of people describe it as "Hawaii-like," with gorgeous scenery, coral reefs, and crystal-clear water.
The bay has numerous recreational facilities, hosts major exhibitions in Sanya, and—randomly—has a giant butterfly center called Butterfly Valley. Most bizarre of all is the 25-meter totem pole in Central Square, which has crazy dragons, fish, and goddesses carved into it.
Even the most glowing marketing for Yalong Bay admits that it's swarmed by tourists, especially during high seasons. If you keep that in mind, it's still a really fun place to visit.