Well, a few calculations, and a bit of by-eye estimations puts the centre of the British Isles ( i.e. including all of Ireland, but not Rockall, the Channel islands or anything further out than Shetland ) somewhwere about Snowdonia or Anglesey.

Although for most people, the centre of the universe is inside their own head, so presumably the centre of the British isles is as well.

This is a really pointless discussion, isn't it?