The Walls of Benin were a combination of ramparts and moats, called Iya in the local language, used as a defense of the defunct Kingdom of Benin, which is present-day Benin City, the capital of present-day Edo, Nigeria. It was considered the largest man-made structure lengthwise and was hailed as the largest earthwork in the world. It is larger than Sungbo's Eredo.[citation needed] It enclosed 2,510 sq. miles (6,500 km²) of community lands. Its length was over 9,900 miles (16,000 km). It was estimated that earliest construction began in 800 and continued into the mid-15th century.

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