Silbury Hill Wiltshire
Silbury Hill near Avebury in Wiltshire is the largest prehistoric man-made mound in Europe, a conical chalk hill approximately 40 metres high and 167 metres in diameter at the base that was built in stages around 2400 BC with a quantity of material sufficient to fill a modern sports stadium. The hill stands enigmatically in the Kennet valley below the great prehistoric ceremonial landscape of Avebury and Windmill Hill, its massive bulk completely lacking any feature that has yet provided a definitive explanation of its purpose, making it one of the most tantalising and most discussed of all British prehistoric monuments. The sheer scale of Silbury Hill, which would have required millions of person-hours of labour to construct, implies a social organisation capable of sustaining an enormous communal building project over an extended period, and the commitment of resources implied by the construction provides evidence for the social complexity of Neolithic Britain that is difficult to account for in simple models of small-scale agricultural communities. The effort involved was not an accident or a casual act but a deliberate programme of construction whose purpose must have been of overwhelming importance to the people who built it. The hill has been investigated several times since the eighteenth century by tunnelling into the interior, most recently in the 1960s, but no burials, artefacts or other evidence of function have been found that explain its purpose. The absence of any discovered reason, combined with the certainty of its enormous cost in human effort, creates the particular fascination that surrounds Silbury Hill and distinguishes it from the more explicable monuments of its period. English Heritage manages the exterior of the hill and the surrounding area; the ancient road that passes the base of the hill provides excellent views of its profile against the Wiltshire sky.