To relieve the tremendous traffic congestion, in 1990 Shanghai began building an elevated highway infrastructure consisting of a box-shaped ring road, bisected by north-south and east-west highways.
為了紓解龐大的交通量，1990 年起，上海市中心建造了一個「口」字型的內環快速道路，加上南北、東西縱橫的「十字架」高速公路，構成一個立體的「申」字型高架公路骨幹。