Old Oyo
Nigeria
Old Oyo, also known as Oyo-Ile, Katunga, Oyo-Oro, and Eyo is the site of a ruined medieval city that was once the capital of the Oyo Empire in what is now modern-day Nigeria. It has been abandoned since 1835. It was a major cultural and political center of West Africa during the empire's height. Established by Yoruba groups migrating from the city of Ile-Ife, the city was the seat of authority for the Alaafin, or custodian/keeper of the palace which was called the Aafin. As the capital of a major state during the 17th and 18th centuries, the city is also the site of large markets such as the Akesan market, which was recreated in the later city of New Oyo. Archaeology has been conducted at this site for over four decades. The area designated as Old Oyo is nearly 3,000 hectares (36,000,000 yd2).
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).