Thanks for the tip. It's a very useful site. However it doesn't appear to show anything, but then with only very vague directions to work with it's tough. I can see that the four stone Druids Altar north of Grassington is shown as a henge on the OS map so these things can be misleading. There are a series of 4-5 cairns further down the valley, on the lower reaches of Conistone Moor, they look very interesting.

Me and my friend Phil ventured up beyond Kettlewell recently and found something called the Hunters Stone. it may or may not be a standing stone, we have no idea. There's a sunblinded photo at the botton left hand corner of http://www.larkfall.co.uk/xetb-pics.htm