Ireland was subject to Viking raids from the end of the 8th century and the Youghal area was no exception. The “Annals of Youghal” record that a site was first inhabited in 853 when the Vikings “entrenched themselves at “Eo-Chaille”….It is recorded that shortly after their arrival a violent storm changed the course of the Blackwater River, which, prior to this had entered the sea at Whiting Bay, Co. Waterford. The tremendous upheaval caused by the storm channeled out a new course forming Youghal Harbour where The Vikings built a fortress and laid the foundations of a commercial sea-port. The Viking settlement of Youghal is likely to have been small and may not have been a permanent foundation.
A stone slab in the Boyle Chapel of St Mary’s Collegiate Church bears the faint etched outline of a longboat.