The Hill of Slane is a historic site located in County Meath, Ireland. It is believed to have been an important religious and ceremonial site for the pre-Christian Celts, and it later became a significant site for the spread of Christianity in Ireland.
St. Patrick, the patron saint of Ireland, is said to have come to the Hill of Slane in the fifth century AD to light the Paschal Fire, a tradition which was forbidden by the High King of Ireland, Laoghaire. Despite the King's orders, St. Patrick lit the fire on the hill, which could be seen for miles around. When the King saw the fire, he summoned St. Patrick to his court at Tara to explain his actions.
St. Patrick used the opportunity to preach the Christian faith to the King and his court, and he is said to have used a shamrock to explain the concept of the Holy Trinity. The King was impressed by St. Patrick's teachings and allowed him to continue his missionary work in Ireland.
The Hill of Slane has since become an important pilgrimage site for Christians, and it is home to a number of religious monuments, including the ruins of a 15th-century friary and a Celtic high cross.