Located in Shangfang Mountain National Forest Park, Yunshui Cave is found 530 meters above sea level at its entrance. It's one of the earliest-developed caves in Beijing. Currently, 613 meters of the cave path have been explored, including seven halls and 108 naturally formed Karst landscapes. Among them, the most famous one is the "Tian Zhu" (which literally means "column reaching the sky"), the highest stalagmite in China. Based in the 2nd hall, "Tian Zhu" stands 38 meters high and eight meters in diameter. On both sides of the stalagmite, there are rows of stalactites of different sizes, which can create music like musical instruments upon beating. In Yunshui Cave, you can see the magic of nature such as the grotesque rocks and musical stalagmites.