Any ideas chaps?
I'm half inclined to suggest going to look at the two coal mines on Anglesey - nothing to see underground, just some surface ruins, but always been intrigued to take a look...
Probably not terribly exciting though.
Or, could nip up to Cefn Du for a look (before they flood it!) or take a look at some of the pits above Glynrhonwy - Cook and Ddol.
Or if it's a nice night take a look at some of the holes on the hill above Sygun.
my orders are to sit here and watch the world go by