Silbury Hill construction is estimated to have involved about 4 million man hours of work and half a million tonnes of material, mostly chalk, to create it.
The mound is located near Avebury in the English county of Wiltshire. It is part of the Stonehenge, Avebury and Associated Sites UNESCO World Heritage Site. It is the tallest prehistoric man-made mound in Europe and one of the largest in the world; similar in size to some of the smaller Egyptian pyramids of the Giza Necropolis.
The monument we see today was not conceived and built in a single campaign, but enlarged over several generations. Perhaps different people brought soil and chalk from their own neighbouring lands, bringing communities together. Over time, the project became more ambitious, with huge quantities of chalk dug from the surrounding ditch to build the mound.
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