The plaque recovered from the flanks of Cadair Idris above Llyn Mwyngi, Tal-y-Llyn... suggest a visit to see it at The National Museum of Wales would be worthwhile.
Image credit: (presumably) National Museum of Wales
location_on
photo
ondemand_video
forum
description
link
Wow, It looks like an alien.
I've read that some scholars reckon it might represent a severed head... the Celts were apparently headhunters holding the knapper in high esteem.