Hey Winterjc,
You spoke the other week about cup and ring markings at Castleton which you didn't find the last time you were there- I was re-reading one of me books and came across these 8 figure map co-ords for the sites. You may know of em already, you might not- hope they're of some use;
NS 85888840,
88518831,
85718797,
85528816,
85558811,
85978826.
Hey- you could borrow FourWinds new GPS to find em ;) otherwise it's the ol' 1:25000 map n sharp pencil time!
Cheery,
TKnow
PS- info from 'Rock Carvings of Northern Britain' by Stan Beckensall (pub. by Shire)