Ten Free Things to do in Dublin: A surprisingly walkable city, Dublin captivates with an unusual mix of bloody historical intrigue and modern vibrant pride. On top of that, the Irish are some of the most welcoming people in the whole world. Though the city offers activities for every budget, from shoestring to high class, this is a list of only free things to do and see in Dublin.
The Tara Brooch is a Celtic brooch of about 700 AD generally considered to be the most impressive of over 50 elaborate Irish brooches to have been discovered. It was found in 1850 and rapidly recognised as one of the most important works of early Christian Irish Insular art; it is now displayed in the National Museum of Ireland in Dublin. http://en.wikipedia.org/wiki/Tara_Brooch
The Mullamast Stone, from 500-600 in Ireland. There are 4 blade marks on the left side of the stone and 2 deep ones on top, suggesting that the stone was used as part of a “sword in the stone” kingship ritual. The perpetuation of the importance of the “sword in the stone,” which comes from Arthurian legend, demonstrates the continuity of Celtic rituals even after the arrival of Christianity in Ireland.