Nigeria boasts a diverse geographical makeup, from wetlands and swamps to mangrove forests and savannas. The country covers a total of 356,000 square miles that are divided into 36 states and one territory. Over 174 million people live in Nigeria, 3 million of which live in Abuja, the capital, as of 2016.
Nigeria, which lies on Africa's west coast bordering the Gulf of Guinea and the Atlantic Ocean, borders Benin on the west, Niger on the north, and Chad and Cameroon on the east. It consists largely of savannas and river valleys. The Niger River Valley runs from Nigeria's west border southeast to the center of the country. The Benue River Valley runs southwest from the country's east border. The two rivers and valleys meet just south of Abuja and run south to the Atlantic Ocean. The river valleys consist of lowlands, making up the bulk of the country.
North of the river valleys lies Nigeria's savanna or broad upland, consisting of three zones: the Guinean forest-savanna mosaic, Sahel savanna and Sudan savanna. The Sahel savanna is just south of lake Chad. Nigeria has a few mountains, such as Chappal Waddi, the highest point of the country at 7,936 feet. Besides the Niger River and Benue River, Nigeria also contains Kaduna River, Kainj Reservoir and Lake Chad.