river, western Ghana, West Africa. It rises near Techiman and flows southward for 250 miles (400 km) to enter the Gulf of Guinea (Atlantic Ocean), at Aby Lagoon, Côte d'Ivoire (Ivory Coast). Its lower course forms the Ghana–Côte d'Ivoire boundary. It is navigable from its mouth for about 60 miles (95 km) to Tanoso, where further travel is blocked by the Sutre Falls. The Tano and the parallel Ankobra drain the western portion of a shallow basin lying southwest of the Kwahu Plateau, the main watershed of Ghana. The Ankobra–Tano Basin is important for mining (gold, bauxite), timber, copra, palm oil, and rubber.