The Tiger Mountain Tunnel with a maximum cross-section of over 400 square meters has been completed and opened to traffic.

On the 27th, it was learned from China Railway Construction Corporation Limited that the Laohushan Tunnel, invested and built by Qingdao City Construction Group and built by China Railway 14th Bureau, was officially opened to traffic. This tunnel is a double-sided eight-lane tunnel with a maximum excavation section exceeding 400 square meters, which is a rare super-large excavation section urban transportation tunnel in China.