This is the story of a lost medieval city you’ve probably never heard about. Benin City, originally known as Edo, was once the capital of a pre-colonial African empire located in what is now southern Nigeria. The Benin empire was one of the oldest and most highly developed states in west Africa, dating back to the 11th century.
The Guinness Book of Records (1974 edition) described the walls of Benin City and its surrounding kingdom as the world’s largest earthworks carried out prior to the mechanical era. According to estimates by the New Scientist’s Fred Pearce, Benin City’s walls were at one point “four times longer than the Great Wall of China, and consumed a hundred times more material than the Great Pyramid of Cheops”.
Situated on a plain, Benin City was enclosed by massive walls in the south and deep ditches in the north. Beyond the city walls, numerous further walls were erected that separated the surroundings of the capital into around 500 distinct villages.
Pearce writes that these walls “extended for some 16,000 km in all, in a mosaic of more than 500 interconnected settlement boundaries. They covered 6,500 sq km and were all dug by the Edo people … They took an estimated 150 million hours of digging to construct, and are perhaps the largest single archaeological phenomenon on the planet”.