Hilary Makins who is the Head Warden for Avebury, and I actually have a formal statement from Hilary by email this morning as follows:

'It is not clear where this information is coming from, but please let us confirm that there is no requirement by the National Trust for any individual to attend any ceremonies during the Lammas weekend or at any other observance. Although some individuals question the necessity to camp overnight by those who do not attend ceremonies. The Trust does not, and would not want to distinguish between those that do and those that do not attend.'

BB
Sian