National Museum Abeokuta is a small but useful stop for understanding Egba history before visiting Ake and Olumo Rock. The collection includes carved objects, regalia, craftwork, and local historical material rather than blockbuster exhibits.
It works best with a guide or staff explanation, since labelling can be limited. Expect a modest entrance fee and a straightforward local museum experience: short, specific, and worth doing if you want more context than the city sights provide on their own.