Zhongnanshan Tunnel

Zhongnanshan Tunnel, or Qinling Zhongnanshan Tunnel in Shaanxi province, China, is the longest two-tube road tunnel in China. It is also the fourth longest road tunnel overall in the world, after the Lærdal Tunnel in Norway, the Yamate Tunnel in Japan and WestConnex in Australia. The long tunnel, crosses under the Zhongnan Mountain. It opened on 20 January 2007, becoming part of the Xi'an-Ankang Highway between Chang'an and Zhashui. The cost to build the tunnel was 3.2 billion yuan. The maximum embedded depth of the tunnel is 1640 metres below surface level.
Unlike other tunnels of its size, the Zhongnanshan Tunnel is not open to the public, rather it was constructed as a means of accessing the Jinping Dam.