Beat me to it Fitz!!! Fantastically useful book, tho worth mentioning that you need OS maps with it at least as much as with Julian's book.
Let's just say like Julian's book, some of Burl's descriptions of how to find the sites are better than others.... (Mind you some ARE just more difficult to find, and at least he never cops out by saying 'needs an OS map'!
This place is by far the best for directions!
love
Moth