Пра
The major drainage divide runs from the southwest part of the Akwapim-Togo Ranges northwest through the Kwahu Plateau and then irregularly westward to the Ivory Coast border. Almost all the rivers and streams north of this divide form part of the Volta system. Extending about 1,600 kilometers in length and draining an area of about 388,000 square kilometers, of which about 158,000 km2 lie within Ghana, the Volta and its tributaries, such as the Afram River and the Oti River, drain more than two thirds of Ghana. To the south of the divide are several smaller, independent rivers. The most important of these are the Pra River, the Tano River, the Ankobra River, the Birim River, and the Densu River. With the exception of smaller streams that dry up in the dry seasons or rivers that empty into inland lakes, all the major rivers in Ghana flow into the Gulf of Guinea directly or as tributaries to other major rivers. The Ankobra and Tano are navigable for considerable distances in their lower reaches.