Ibadan is the capital and most populous city of Oyo State, in Nigeria. It is the third-largest city by population in Nigeria after Lagos and Kano, with a total population of 3,649,000 as of 2021, and over 6 million people within its metropolitan area. It is the country's largest city by geographical 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 located in south-western Nigeria, 128 kilometres (80 mi) inland northeast of Lagos and 530 kilometres (330 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.