a landlocked republic in West Africa: important since earliest times for its trans-Saharan trade routes; made a French colony in 1922 and became fully independent in 1960; exports peanuts and livestock. Official language: French; Hausa is also widely spoken. Religion: Muslim majority. Currency: franc. Capital: Niamey. Pop: 21 477 348 (2017 est). Area: 1 267 000 sq km (489 000 sq miles)

a river in West Africa, rising in S Guinea and flowing in a great northward curve through Mali, then southwest through Niger and Nigeria to the Gulf of Guinea: the third longest river in Africa, with the largest delta, covering an area of 36 260 sq km (14 000 sq miles). Length: 4184 km (2600 miles)

a state of W central Nigeria. Capital: Minna. Pop: 3 950 249 (2006). Area: 76 363 sq km (29 476 sq miles)