Around 3,000 years ago, people were going about their business in a marshy corner of eastern England known as The Fens.
These Fenland folk had just built their settlement over a slow-moving river channel, sinking wooden stilts for homes deep into the squishy soil. They had erected a wooden palisade around it all, creating as comfortable a gated community as one might imagine possible in a setting that was, well, a bit swampy.