The 33.8km line links Longjiang in the west with Xianlinhu in the east and serves 18 stations including interchanges with lines 1, 2 and 3.

The Yuan 20.8bn ($US 3bn) line includes a 32.3km underground section with the remaining 1.5km running on surface and elevated alignments. Services are operated by a fleet of Type B metro trains.

The opening of Line 4 takes the total length of Nanjing’s metro network to 258km with 139 stations.