In China, Xinxiang-Jincheng Expressway (Xinjin Expressway) with world's longest spiral tunnel, the Hankou Tunnel has opened. It was built by China Construction Communications Engineering Group Co Ltd(CCCEG), a subsidiary of China State Construction Engineering Corporation (CSCEC).

There is almost 110 meters of level difference between the entrance and the exit of the tunnel. The left tube of the tunnel is reported 4,457 meters long and right is 4,366 meters.

http://en.sasac.gov.cn/2023/04/21/c_15144.htm