Lin Biao
A system of tunnels with meeting rooms, offices for the top commanders (including the Commander in Chief, Mao Zedong and the second in command, Lin Biao), communication center, etc., were constructed under one of the hills in the area, and villas for Mao Zedong and Lin Biao were built on the surface. However, after the death of Lin Biao and the arrest of Huang Yongsheng in September 1971, the project was terminated, and it never saw its intended use. Neither Mao nor Lin Biao ever actually visited the site.