Yongdusan is located on the seaside of Longtan Cave in the center of Jeju City. It is a rock formed by the cooling after the lava eruption 2 million years ago. It is precisely because the rock is quite like a faucet at one end, so it is named the faucet. It is a symbol of Jeju tourism, the starting point of the coastal road, and the most prominent piece of rock on the west coast of Jeju Island. About 200 meters east of the faucet rock, there is a dragon pool, which is said to be a place where dragons play, so the name of the dragon pool is also called Longyuan. The pool water is crystal clear.