Underground City (Beijing)

The Underground City (Chinese: 地下城; pinyin: Dìxià Chéng) is a Cold War era bomb shelter consisting of a of tunnels located beneath Beijing, China. It has also been referred to as the Underground Great Wall since it was built for the purpose of military defense. The complex was constructed from 1969 to 1979 in anticipation of a nuclear war with the Soviet Union, as Sino-Soviet relations worsened and was officially reopened in 2000. Visitors were allowed to tour portions of the complex, which has been described as "dark, damp, and genuinely eerie". Dixia Cheng has been closed for renovation since at least February 2008.

The tunnels of the Underground City 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. Many of the entrances have since been demolished or blocked off for reconstruction. Known remaining 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.

At the height of Soviet-Chinese tensions in 1969, Chinese chairman Mao Zedong ordered the construction of the Underground City during the border conflict over Zhenbao Island in the Heilongjiang River. The Underground City was designed to withstand nuclear, biochemical and conventional attacks. The complex would protect Beijing's population, and allow government officials to evacuate in the event of an attack on the city. The government claimed that the tunnels could accommodate all of Beijing's six million inhabitants upon its completion.

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