Walls of Benin

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. 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.

The walls were built of a ditch and dike structure; the ditch dug to form an inner moat with the excavated earth used to form the exterior rampart.

The Benin Walls were ravaged by the British in 1897 during what has come to be called the Punitive expedition. Scattered pieces of the structure remain in Edo, with the vast majority of them being used by the locals for building purposes. What remains of the wall itself continues to be torn down for real estate developments.

The Walls of Benin City was the world's largest man-made earth structure. Fred Pearce wrote in New Scientist:

They extend for some 9,900 miles (16,000 kilometres) in all, in a mosaic of more than 500 interconnected settlement boundaries. They cover 2,510 sq. miles (6,500 square kilometres) and were all dug by the Edo people. In all, they are four times longer than the Great Wall of China, and consumed a hundred times more material than the Great Pyramid of Cheops. They took an estimated 150 million hours of digging to construct, and are perhaps the largest single archaeological phenomenon on the planet.

This site was added, along with Sungbo's Eredo, to the UNESCO World Heritage Tentative List on 1 November 1995 in the Cultural category.

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