The best known are Koroko, Kong and Bona, entrepots for the trade of the middle Niger, and Bontuku, on the caravan route to Sokoto and the meeting-place of the merchants from Kong and Timbuktu engaged in the kola-nut trade with Ashanti and the Gold Coast.
Caffeine (formerly known as theme) is the alkaloid of tea, and is identical with that of coffee, guarana, mate and kola nut.
Formerly one of the great slave and ivory marts of West Africa, it is now a centre of the kola-nut commerce and a depot for government stores.
The wealth of the country consists, however, chiefly in its indigenous trees of economic value - the oil-palm, the kola-nut tree and various kinds of rubber plants, chiefly the Landolphia owariensis.
The oil-palm and kola-nut tree are especially abundant in the Sherbro district and its hinterland, the Mendi country.