Waterford City in Ireland , (68 images) Waterford is the oldest city in Ireland. A walled city of Viking origins, it retains much of it's medieval character together with the graceful buildings from its 18th century expansion. The parameters of the 10th century settlement can be clearly identified in The Viking Triangle. Reginald's Tower is the most historic urban medieval monument in Ireland. Photo: Knut Øyvin Skaar