Jinjiazhuang Tunnel

Jinjiazhuang Tunnel or Jinjiazhuang Spiral Tunnel, is the world's longest highway spiral tunnel. The spiral has a curve radius of 860 m and the elevation difference between the tunnel entrance and exit is 112 m.

The tunnel is on S3801 Beijing-Chongli Expressway. The Expressway is the main route from the Yanqing cluster to the Chongli cluster of the Beijing 2022 Winter Olympics.