Seoul City Route 21 (Trunk)
| Seoul Special Metropolitan City Route 21 | |
|---|---|
| 서울특별시도 제21호선 | |
| Siheung - Jungnim Line | |
| Route information | |
| Length | 17.7 km (11.0 mi) |
| Major junctions | |
| From | Geumcheon District, Seoul |
| To | Jung District, Seoul |
| Location | |
| Country | South Korea |
| Highway system | |
Seoul Metropolitan City Route 21 (Korean: 서울특별시도 제21호선) is a road located in Seoul, South Korea. With a total length of 17.7 km (11.0 mi), this road starts from the Siheung-dong in Geumcheon District, Seoul to Jungnim-dong in Jung District.