The Benin Moat (Iya in the local language) was built as a defensive fortification around Benin City in the great Kingdom during the time it was at its height and when the kingdom engaged in many wars. Considered one of the great wonders of the world, the walls were built of a ditch and dike structure. The ditch was dug to form an inner moat and the excavated earth from this was used to construct the external rampart. Its construction method predates the use of modern earth-moving equipment or technology.