Silbury Hill - Credit: Wikimedia Commons
Silbury Hill is a prehistoric artificial chalk mound near Avebury in the English county of Wiltshire. It is part of the Stonehenge, Avebury and Associated Sites UNESCO World Heritage Site. At high, it is the tallest prehistoric human-made mound in EuropeAtkinson 1967. and one of the largest in the world; similar in volume to contemporary Egyptian pyramids.Malone (1989), p. 95. Read more on Wikipedia
Source: en.wikipedia.org