Gianh River
The Gianh River is a river in the Quảng Bình province of Vietnam's North [Central Coast]. The river is in length.
The Gianh–Son River served as the boundary between Đàng Ngoài and Đàng Trong, ruled by rival families, during the partition of Vietnam in the 17th and 18th centuries following the Trịnh–Nguyễn War. The 17th parallel, used as the border between North Vietnam and South Vietnam from 1954 to 1975, was located just south of the Gianh River, at the Bến Hải River in Quảng Trị province.