It is an important location in the eastern part of Xixi Wetland Park. It is entered from Fudi through Hejing Ancient Street and is the ticket office of Shentankou. The reason for the name is that this place used to be a very deep pool, but now because of the green water, I can't see the bottom of the river and I don't know the depth. There are two major natural and artificial points, the former is a hundred-year-old eucalyptus tree surrounded the shore, the environment is particularly quiet; The latter is the famous film "If You Are the One" once shot here, and now there are still small boats in the pool for shooting at that time, and there are red heart-shaped declaration walls that are especially grabbing mirrors.