Walls and ditches over 160 km long round the Ijebu heartland, south-west of Ijebu Ode; on Nigeria's UNESCO tentative list; dating disputed (10th–11th century per Darling; late 14th–early 15th century per later excavations); legend of Bilikisu Sungbo, whose grave is believed to be at Oke-Eiri; annual pilgrimage. Accessed 2026-10-02.