Why does Changzhou Longcheng Elevated Road need a tunnel?

The mountain can't move. According to the person in charge of the tunnel project, the tunnel was built because the mountain could not be cleared, and the area of the mountain was too large, which required most manpower, material resources and financial resources to clear it. A tunnel is a building built underground, underwater or in the mountains, laying a railway or building a highway for the passage of motor vehicles. Its location can be divided into three categories: mountain tunnels, underwater tunnels and urban tunnels.