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.