Ngazargamu, Birni Ngazargamu, Birnin Gazargamu, Gazargamo or N'gazargamu, was the capital of the Bornu Empire from ca. 1460 to 1809. Situated 150 km (93 mi) west of Lake Chad in the Yobe State of modern Nigeria, the remains of the former capital city are still visible. The surrounding wall is 6.6 km (4.1 mi) long and in parts it is still up to 5 m (16 ft) high.