I went there at the end of November last year, just in time for free activities. I went to this place because I saw the pictures taken by others. I was really shocked by the huge underground caves. I didn't know how to dig such a large cave without modern machinery and equipment in ancient times, and the wall patterns were very neat. Whether people look from top to bottom or from bottom to top, they will have a somewhat inexplicable sense of fear, because it is too deep. Do not miss ancient relics if you like to see them.