Cahokia

You settled the fertile floodplain of the Mississippi valley one-and-a-half thousand years ago.

After five hundred years of stable occupation, your numbers suddenly exploded. You created a magnificent city with over a hundred mounds linked by community plazas. Your workers took decades to realise this vision. With no pack animals or wheel, they hauled the earth by hand; the largest pyramid, Monks Mound, took more than fourteen million baskets of soil.

By 1250, your culture was one of the most advanced in ancient America and your population was larger than London’s. But it was not a peaceful time; you built a stockade around the city centre, and archaeologists found the largest mass grave in the Americas; with the bodies of those who had been brutally killed, others buried alive.

As your rising population put more and more pressure on the land, you deforested river edges, causing them to erode. The resulting floods made cropland too marshy for corn. Wood ran low. The oak and hickory you burned in the early centuries was replaced by energy-poor softwoods.

Your city went into decline and the population dropped away until, six hundred years ago, you abandoned it, leaving no record of your language or your culture’s real name.