Did you know that in 1010 AD, the largest man-made structure in Africa was located in the Old Benin Kingdom, in present-day Nigeria? The mighty Walls of Benin – in their prime – stretched 16,000 km (beaten only by the Great Wall of China’s 21,000 km!). Alas, this glorious kingdom was destroyed – and looted – by the British. Here’s a quick look at the key history of one of the world’s engineering wonders.