Lagos is the most populous city in Nigeria and the second-largest city in Africa after Kinshasa, Democratic Republic of the Congo, having a population of 14.8 million as of 2021 within the city proper. The Lagos metropolitan area has a total population of 21.3 million, making it the second-largest metropolitan area in Africa, after Cairo.
Lagos is a major African financial centre and is the economic hub of Lagos State and Nigeria at large. The megacity has the fourth-highest GDP in Africa and houses one of the largest and busiest seaports on the continent. It is one of the fastest growing cities in the world.