Entrance of Hebei Jinjiazhuang Extra-long Spiral Tunnel in Yanqing-Chongli Expressway is located at east of Zhuanlou Village, Paoliang Town, Chicheng County and northwest of Jinjiazhuang Village, exit at Qipanlaing, Chongli Zone.
Jinjiazhuang Tunnel or Jinjiazhuang Spiral Tunnel, is the world's longest highway spiral tunnel.
The spiral has a curve radius of 860 metres (2,820 ft) and the elevation difference between the tunnel entrance and exit is 112 metres (367 ft).
The tunnel and the Yanchong Expressway will form the main route from Beijing to the Yanqing cluster of the Beijing 2022 Winter Olympics.
According to scrbg.com