| Line 4, Nanjing Metro | |
|---|---|
| 4 | |
| Overview | |
| Type | Rapid transit |
| Status | In operation |
| Locale | Nanjing, China |
| Stations | 18 |
| Operation | |
| Opened | January 18, 2017 |
| Operator(s) | Nanjing Metro |
| Technical | |
| Line length | 33.5 km (20.8 mi) |
| Number of tracks | 2 |
| Track gauge | 1,435 mm (4 ft 8 1⁄2 in) |
Line 4 is a line on the Nanjing Metro system in China. Currently, 18 stations spanning a total of 33.5 km have been constructed for phase one. The line is colored purple as it runs near the Purple Mountain.