The Tuatha Dé Danann had travelled to the “Northern Isles” where they learned many skills and magic in its four cities Falias, Gorias, Murias and Findias. From there they travelled to Ireland bringing with them a treasure from each city – the four legendary treasures of Ireland. From Falias came the Lia Fáil. The other three treasures are the Claíomh Solais or Sword of Light, the Sleá Bua or Spear of Lugh and the Coire Dagdae or The Dagda’s Cauldron.
Source: Lia Fáil – Wikipedia