I recently stayed with a friend who lives in Tignabruaich, a beautiful place on the the Cowal peninsular in Argyl.
O.S. maps indicated cup and ring marks nearby and after an exhausting, wet and muddy search, we eventually found them.
Strange, aren't they? And reading up on them only made them more enigmatic. Ritualistic? Tribal territory indicaters? Astronomical records? Calenders? Decoration?
Whatever their purpose, given the hardness of the material, they weren't done on a whim.
What do you reckon?

I thought they were just something that appeared on my table after a good party... Better do some reading!