The Hankou Tunnel of the Jincheng-Xinxiang Expressway, constructed by CSCEC Road and Bridge Group co, was recently certified by Guinness World Records as the world's longest spiral highway tunnel.

With a total length of 69.75 kilometers, the Jincheng-Xinxiang Expressway starts from Yingpan village, Lingchuan county, Jincheng, Shanxi province, and ends at Kuaicunying village, Fengquan district, Xinxiang, Henan province. It was completed and opened to traffic on Dec 26, 2022, connecting Shanxi and Henan provinces along the Taihang Mountains.

The Hankou Tunnel obtains certification from Guinness World Records. [Photo/Taihang Daily]

The spiral tunnel group of the Jincheng-Xinxiang Expressway consists of nine tunnels, with a total length of 28 km. The entire tunnel group is like a spiral line, winding and rising in two and a half circles in the Taihang Mountains.

Among them, the Hankou Tunnel located in the Taihang Mountains in Xinxiang, is the longest spiral tunnel, with a total length of 4,457 meters, ranging from 784 meters to 893 meters above sea level. It has a height variation of 109 meters between the entrance and exit and a minimum turning radius of 700 meters. It is called a spiral tunnel because the tunnel is designed with small-radius circular curves, which solves the problem of climbing the mountains in a spiral way.

The opening of the tunnel has significantly strengthened transportation, logistics, tourism, and industrial and agricultural production between Shanxi and Henan provinces.