Xiaozhai Tiankeng is a national AAAA scenic spot, located in Xiaozhai village, Xinglong Town, 70 km away from Fengjie County. Tiankeng is the deepest and largest karst funnel in the world with a diameter of 626 meters at the mouth, a diameter of 522 meters at the bottom, a vertical height of 666.2 meters and a total volume of 119 million cubic meters. Tiankengkou is surrounded by cliffs, which are as magnificent as an axe. The rock patterns on the cliffs are peculiar in color, red, yellow and black, just like the traditional Chinese paintings on the cliffs. There are countless deep and unpredictable caves and a surging underground river in the pit. There is a winding staircase from the pit mouth to the pit bottom, with a total length of 2.8 km and 2800 multi-level steps. Looking up from the pit bottom to the pit mouth is like "sitting in a well watching the sky". In 1999, xiaozhaitiankeng was listed in the "World Natural Heritage preliminary list" by the United Nations. In early 2004, it was officially approved as "national key scenic spot" by the State Council。
