d most populous city of Oyo State, in Nigeria. It is the third largest city by population in Nigeria with a total population of roughly 3,649,000 as of 2021[citation needed], and nearly 2 million within its metropolitan area[citation needed]. At 3,080 square kilometres it is the country's largest city by land area. At the time of Nigeria's independence in 1960, Ibadan was the largest and most populous city in the country, and the second-most populous in Africa behind Cairo. Ibadan is ranked one of the fastest-growing cities in sub-Saharan Africa, according to the UN Human Settlements Program (2022). It is also ranked third in West Africa in the tech startups index. Ibadan joined the UNESCO Global Network of Learning Cities in 2016. During the 19th century, Ibadan was the capital of the Ibadan Republic, one of the most powerful states of contemporary Yorubaland. Oyo State Secretariat located in Ibadan Ibadan is located in southwestern Nigeria, 120 kilometres (75 mi) inland northeast of Lagos and 440 kilometres (270 mi) southwest of Abuja, the federal capital. It is a prominent transit point between the coastal region and areas in the hinterland of the country as well as one of Nigeria's most important commercial and research centres. Ibadan was the administrative centre of the old Western Region since the early days of British colonial rule, and parts of the city's ancient protective walls still stand to this day. The principal inhabitants of the city are the Yoruba people, as well as vari