Why it looks like this

Ibadan was founded around 1829 as a war camp during the Yoruba wars, and grew on its seven hills into the largest indigenous city in West Africa — for a long time the biggest city in sub-Saharan Africa. Its historic core was built by its own people, compound by compound: a dense, brown-roofed maze that no colonial planner ever gridded.

British-era additions ring the old city — the railway (arrived 1901), the government reservation's leafy curves, and the University of Ibadan, Nigeria's first — so the map reads inside-out compared to coastal colonial capitals: indigenous centre, planned edges.