See the Spectacular Water Caves
There are lots of karst mountains around Yangshuo, most of which have water caves inside. The caves are spectacular, with different stalagmites and stalactites.
Water cave is one of the common kinds of caves, which is solution cave. This type of cave forms out of limestone. Limestone is a soft rock, even though it feels hard. The limestone is porous enough for water to slowly seep through it, kind of like a sponge. After a long time, the water dissolves enough limestone to hollow out underground tunnels. When these tunnels join together, they make long passageways and underground rooms.
There're a lot of drops of the water falling down from the ceiling of the caves. This kind of drops of water mixed with dissolved limestone. After these drops land, the water evaporates, leaving the limestone. After a long time the tiny limestone drops pile up, and become stalagmites and stalactites. Stalagmite grow up from the ground. Stalactite grow down from the ceiling. An easy way to remember the difference between the stalagmite and the stalactite is that: You "might" trip over a stalagmite, and the stalactite have to hold on "tight" to the ceiling. If a stalagmite and a stalactite connect in the middle, that is a column.
They are really good places to visit and explore.
Among many water caves, Longmen Water Cave is the longest and the most exciting one. Longmen Water Cave is about nine kilometres south of Yangshuo, near Moon Hill. It is about three kilometres long and runs through three mountains. There is a underground river inside the cave. You can take a mud bath inside the cave, it is said that the mud contains many healthy elements. After the mud bath you can have a common bath in the natural swimming pool, whose water is cool, crystal clean and running.