Now that the hysteria surrounding the mention of Terry has died down and any implied delusions made by others have been officially dismissed, I shall add to my previous post.

The NT flyer, Avebury Events - 2009, under the Summer talks, walks and workshops says.....

Festival of British Archaeology - July 18th - August 2nd

Meet the experts Sundays with our curator and our archaeologist. Taster tours around the Stone Circle Afternoon Rambles through the Avebury landscape with our Archaeologists or our Museum Curator.
Let the children discover their inner archaeologist with our mini-digs and other family activities.
Please telephone 01672 539 250 for more details.

For those who would like to read the official NT response to the campsite/tented accommodation during Periodic Observances at Avebury, a downloadable pdf is available here

http://www.nationaltrust.org.uk/main/w-avebury_camp_consult.pdf