Introduction to Heilongtan Waterfall: To the north of Heilongtan is Dongbaizhang Cliff, where the waterfall flows straight into the cave under the cliff. Due to the impact of streams all year round, the cave has a large belly and a small mouth. It is shaped like a tile altar, several feet deep and wide, and is connected to the Dragon Palace of the East China Sea, hence its name. Black Dragon Pool is located in the north of Bailong Pool in Mount Tai. There is West Baizhang Cliff to the west of the pool and South Baizhang Cliff to the southwest. Every summer and autumn, when the rain continues, the three waterfalls are like jade dragons descending from the top of the cliff, which was called "Three Appearances of Clouds and Dragons" in ancient times.