An expressway in the Xinjiang Uygur autonomous region opened to traffic on Friday, making its 22.13-kilometer tunnel officially the world's longest.

The Tianshan Shengli Tunnel traverses the Tianshan Mountains and helps cut the travel time from Urumqi to Korla in half.

The expressway provides a convenient highway connection between northern and southern Xinjiang, linking Urumqi with Yuli county of the Bayingolin Mongolian autonomous prefecture. At the time of opening, public vehicles except medium and heavy-duty trucks are allowed to use the route. The expressway will formally begin trial operation on Jan 1.