Chart and table of population level and growth rate for the Port Harcourt, Nigeria metro area from 1950 to 2025.

Nigeria is the African country with the largest population, counting over 230 million people. As of 2024, the largest city in Nigeria was Lagos, which is also the largest city in sub-Saharan Africa in terms of population size. The city counts more than nine million inhabitants, whereas Kano, the second most populous city, registers around 3.6 million inhabitants. Lagos is the main financial, cultural, and educational center in the country. Where Africa’s urban population is booming The metropolitan area of Lagos is also among the largest urban agglomerations in the world. Besides Lagos, another most populated citiy in Africa is Cairo, in Egypt. However, Africa’s urban population is booming in other relatively smaller cities. For instance, the population of Bujumbura, in Burundi, could grow by 123 percent between 2020 and 2035, making it the fastest growing city in Africa and likely in the world. Similarly, Zinder, in Niger, could reach over one million inhabitants by 2035, the second fastest growing city. Demographic urban shift More than half of the world’s population lives in urban areas. In the next decades, this will increase, especially in Africa and Asia. In 2020, over 80 percent of the population in Northern America was living in urban areas, the highest share in the world. In Africa, the degree of urbanization was about 40 percent, the lowest among all continents. Meeting the needs of a fast-growing population can be a challenge, especially in low-income countries. Therefore, there will be a growing necessity to implement policies to sustainably improve people’s lives in rural and urban areas.

The Egyptian area of Cairo‑Alexandria‑Suhag was the largest city cluster in Africa as of 2021. Considering the over 1,000 cities that are part of the cluster (cities with over 30,000 residents that are within 100 kilometers' distance, adding up to a population of over 2.5 million), the area counted around 92 million inhabitants. The clusters of Lagos‑Ibadan‑Cotonou and Onitsha‑Uyo‑Port Harcourt in Nigeria followed, accounting for approximately 46 million and 43 million residents, respectively.

Social demographic characteristic of adolescents in Port Harcourt, Rivers State.