I’ve saw these sites some 20 years ago. They were SO interesting. I hadn’t know the Irish Celts were so old.
CC
Before they got to Ireland, Scotland, Cornwall, northern France and Wales, the Celts lived all over Europe. They were even in Serbia for a while. Near Belgrade, at the confluence of the Danube and the Sava Rivers, the Roman fortification there was built on Celtic ruins. The Serbs think of the Irish as cousins and they love Irish music.