I was recently watching a documentary about 'Britain's Pompeii' at Must Farm - a rapidly-burned settlement of stilt houses built in a marsh that was preserved by the speed of its destruction.
This set my wife and I to wondering - how on earth were the enormous wooden piles these homes were built on driven into the silt of the marsh they were found in? When you consider Stonehenge or the Pyramids, I can visualise wooden rollers, simple crane and lever mechanisms, that sort of thing, on solid ground. But I simply can't get my head around the process of digging deep holes and somehow hammering what are basically tree trunks into the marsh. Is there any historical evidence for how this was achieved?
I was digging at an Iron Age bridge in Denmark, where we found parts of something that was basically a wooden manchet which would fit around the top of a supporting pillar with wooden spokes sticking out the sides in a cross pattern. Similar implements are still used by fishermen to ram down big stakes for fishing weirs. The long spokes can be used for pulling the posts down into soft sediment with multiple people, or to basically drill a post down by rotating, or I could imagine some kind of rope/pulley system. In our case, with soft sediments on top of sandy layers, no digging was required.