Image of Smerwick Harbor, Republic of Ireland. Smerwick Harbor (Ard na Caithne in Irish) is in a Gaeltacht area on the Dingle Peninsula in County Kerry Ireland. Recently the area has come to be called the "True Gaeltacht". .In the long history of England's attempt to conquor Ireland, Dún Na Óir (Fort of Gold) is famous for the Siege of Smerwick in 1580. A 600 man army comprised of Spanish, Italian, Irish, and English Catholic soldiers came ashore here and occupied Dún na Óir- an iron age promontory fort. The English assaulted the point from land and Smerwick Harbor and succeeded in forcing the garrison to surrender. After their surrender, the entire force was put to the sword. Thereafter the small field beside the fort was known as "Field of the Cuttings" or "Field of the Heads".