From Lacra C the terrier and I headed across the fields in search of the elusive avenues. After crossing some boggy low ground we came across a group of stones that more or less fitted Burls description of 'a few footballish boulders'. The eye of faith is definitely required here but given enough to-ing and fro-ing it is possible to make out an avenue. Saying that, if Mr Burl had said that they were just a fortuitous arrangement of boulders I would also agree with him.
I'm not too sure what to say about this site other than have a look for yourself and see what you think.