There's plenty of woods around away from the roads, the actual Kilmartin valley with the main monuments is a bit to open and you'd be there for all to see, but up in the surrounding hills and woods i can't imagine you'd have any problems at all, just leave no trace, but i'm sure you don't anyway, it's a very special place all around the area, and some of the oldest farming in Scotland went on there and the massive monuments in the valley seem to be giving thanks, offerings and even the dead because of the strong fertility that exists there to this very day.
