I should explain the title. I live in North Nottinghamshire close to the River Trent. The Aegir is a tidal surge that travels up the River Trent about twice a year due to its banks narrowing the further inland it gets. The Aegir is basically a large wave that travels very fast upstream. Before it appears the current slows down, stops, then starts to flow in the opposite direction. It's all very spooky! We tried to chase it once from the river bank, me, my girlfriend, her dad and his dog, in a landrover. He doesn't take prisoners in his landrover, yet we still couldn't catch the wave. King Cnut sat on the same river bank and watched the same wave nearly a thousand years ago.