Introduction to Thunder Sky: The second cave "Thunder Sky" is more than 800 meters long. There are two waterfalls outside the cave and one waterfall inside the cave. The sound is like thunder, hence the name. There are also "stone flowers" on the top of the cave. It is a spectacle. Every year around the Dragon Boat Festival, nearby people come to watch the "Stone Blossom". Every year, tens of thousands of visitors come, forming a traditional custom.