Trespassing UFO hunters have climbed into Silbury Hill in Wiltshire, UK, damaging the biggest man-made Neolithic mound in Europe. English Heritage closed the 4,000-year-old mound to the public after an 18th Century mining shaft opened up in the summit in May last year.
      The alien hunters broke into the site under cover of darkness soon after the hole was discovered. Evidence of the trespass has only come to light now, after a video of the foray was included in a documentary film. After tunnelling under the temporary roof installed by English Heritage, two climbers abseiled into the shaft, while a third videoed the stunt. They repeated the climb on a rainy winter night six months later.
      Archaeologist Mike Pitts says the climbers dislodged the soft clay sides of the unstable shaft, possibly damaging vital archaeological clues. "They were extremely lucky to come out again alive. Between their two visits there was a major collapse, which they joked about in the video of their December visit."
      Footage of the illicit descent has since been incorporated into a video by Dutch documentary makers Janet Ossebaard and Bert Janssen, who have attempted to sell it on the tourist circuit in nearby Avebury. Mr Pitts says that not only have shopkeepers refused to stock the video, the crop circle enthusiasts who flock to Wiltshire every summer have almost universally condemned the stunt. The documentary makers complained on a Dutch national paper that because of all the negative publicity it has become near impossible for them to work in England and they lamented the fact that there are calls that they should pay for the damage.
      As repairs to the hill get under way, English Heritage is carrying out a seismic study to create a 3D computer image of what lies inside. It is the latest attempt to unlock the secrets of the hill, which forms part of the ancient landscape surrounding Avebury stone circle and nearby Stonehenge.

Sources: BBC News (28 August 2001), Algemeen Dagblad (8 September 2001), Stones Mailing List (12 September 2001)