Of all the historical landmarks spread throughout the British Isles Silbury Hill is one of the most remarkable. Accepted as the largest man-made mound in pre-industrial Europe it has a symmetry that makes it seem almost modern….on seeing it for the first-time the uninformed visitor can get quite a surprise on learning of its antiquity.
At 130 feet high and covering an area in excess of 5 acres the enormous contours of the hill still challenge us with the mystery of why it was built and what for, but the solution to the mystery of how it has survived for 4,500 years without eroding away has been known from some early excavations. Surrounding the base of the hill is an extensive ditch which is elongated on the western flank. It is believed that it may have been deliberately filled with water when Silbury was first constructed. A number of tunnels have been dug into the hill commencing in 1776 when the Duke of Northumberland employed Cornish tin miners to sink a shaft from the top of the hill. This particular shaft seems to have contributed to a disaster for the hill when on May 29th. 2000 a large hole nearly 20m deep appeared on the summit. Although the various tunnels and excavations over the years have failed to produce any solution as to the purpose of Silbury they have revealed that the hill was built in three stages starting with a primary mound about 16 feet high and 120 feet in diameter. Accurate dating for the construction has proved difficult to achieve but carbon dating of some antler-pick remains recently found at the summit of the hill indicate that its construction was completed about 2500 BC which pre-dates the building of the avenues by about a century. The year of its birth may never be known with any certainty but evidence obtained from remnants of insects which were found in the hill’s base layer indicate that the building of Silbury probably commenced during the month of August. There is evidence that a substantial Roman building once existed adjacent to the base of the hill on its southern side and recent surveys have now revealed that an extensive Roman settlement surrounded the road adjacent to the hill. Quite what the Romans thought about Silbury poses an interesting question…… they certainly used it as a marker when constructing the adjacent A4 road though it is hard to imagine that it didn’t play a more substantial role in their lives at some time.