Adamawa is a state in the North-East geopolitical zone of Nigeria, bordered by Borno to the northwest, Gombe to the west, and Taraba to the southwest while its eastern border forms part of the national border with Cameroon. It takes its name from the historic emirate of Adamawa, with the emirate's old capital of Yola serving as the capital city of Adamawa State. The state was formed in 1991 when the former Gongola State was broken up into Adamawa and Taraba states. The state is one of the most heterogeneous in Nigeria, having over 100 indigenous ethnic groups.
Of the 36 states, Adamawa is the eighth largest in the area, but the thirteenth least populous with an estimated population of about 4.25 million as of 2016. Geographically, the state is mainly composed of highlands and mountains (the Atlantika, Mandara, and the Shebshi ranges) and the Adamawa Plateau crossed by valleys and rivers, most notably the Benue and Gongola rivers. The lowlands of Adamawa are all part of the West Sudanian savanna in the north and the wetter Guinean forest-savanna mosaic in parts of the south, while elevated areas are parts of the Mandara Plateau mosaic and Cameroonian Highlands forests ecoregions. In the extreme south of the state is part of the Gashaka Gumti National Park, a large wildlife park that contains large populations of bushbuck, African buffalo, patas monkey, black-and-white colobus, giant pangolin, and hippopotamus along with some of Nigeria's last remaining Nigeria-Cameroon chimpanzee, African leopard, and African golden cat populations.