Location
The tunnels comprising Dixia Cheng run beneath Beijing's city center, covering an area of 85 square kilometres (33 sq mi) 8 to 18 metres (26–59 ft) under the surface. At one time there were about 90 entrances to the complex, all of which were hidden in shops along the main streets of Qianmen. Known entrances include 62 West Damochang Street in Qianmen, Beijing Qianmen Carpet Factory at 44 Xingfu Dajie in Chongwen District, and 18 Dazhalan Jie in Qianmen.
Read more about this topic: Underground City (Beijing)