On 14th and 15th July 2007, a unique experiment took place at Silbury Hill, in Wiltshire, England.

Silbury Hill was built in the Neolithic period or 'late stone age' - some 4600 years ago. It is an enormous structure - a conical, flat-topped hill 130 feet high and 550 feet in diameter. Its construction was an amazing feat of skill and organization that would be difficult even today. The people who built Silbury used only human labour; with no tools other than antler picks and baskets, and no draught animals. With an inner structure of chalk blocks covered with rubble and earth, the work involved its construction is difficult to comprehend: the labour has been estimated at 4 million man-hours.

But why did the builders go to so much trouble?
The true purpose of Silbury Hill is still a mystery. Several hundred years of investigation by treasure-hunters and archaeologists has resulted in nothing except a weakening of the structure, which is riddled with tunnels and in danger of collapsing. Under the direction of English Heritage, work has finally begun on conducting a full survey of the hill and the surrounding area; then back-filling the old tunnels with chalk. The work seems frought with difficulties though and unusually wet weather has brought extra problems.

(Update: the work was finally completed in 2008)

A superb Avebury website: Avebury



Archaeoacoustics is a very new way of considering our past, but English Heritage archaeologists have been investigating the acoustics of archaeological sites and attempting to discover features that might point to their function as perfomance spaces. The Acoustic Silbury event was a part of that work.
Ancient music specialists Simon & Maria O'Dwyer played a selection of replica instruments (dating from the stone age to the iron age) from the top of the hill, in five performances over the course of a weekend.
Members of the public were invited to help by listening in various positions around the hill and noting what could be heard. I was one of them, and managed to also make binaural recordings of the performances from three different positions around Silbury - one of them half a mile away, on Waden Hill.
Some of the results can be heard here as mp3s.
My final recording was of the 11am Sunday performance and brought some unexpected and very exciting results. From a position close to the hill, on its north side (photo above) I recorded some very spectacular repeat echoes, of about half a second in length, coming from the surrounding hills. I have spent a lot of time around Silbury, but was previously unaware of any echoes. The effect is very dramatic and may have been a factor in the siting of the hill.

Plug in a pair of headphones and listen for yourself...

Silbury Hill is just one element of an ancient and greater 'ritual landscape' known as the Avebury Complex. The monuments in the surrounding area were built over a period of several thousand years. To the northwest is Windmill Hill - site of a community that thrived around 3500 BC. A mile to the north of Silbury is the great Avebury stone circle and its avenue of standing stones, dating from 3000 BC. To the southeast is the West Kennet long barrow - used for burials for several hundred years and sealed shut around 3300 BC. The whole area around Avebury is littered with later monuments, such as the round barrows of the bronze age.


Copyright Steve Marshall 2007. Map is OS Explorer 157 - Crown Copyright