On the east bank of the River Barrow is St. Mullin's, a monastery which was founded by St. Moling; a prince, poet, artist and artisan, as well as a priest, who died in 696. He became Bishop of Ferns and was buried at St. Mullin's. The monastery was plundered by the Vikings in 951 and was burned in 1138. An abbey was built on the site later, in the Middle Ages. In an 8th Century manuscript known as "The Book of Mulling", there is a plan of the monastery - the earliest known plan of an Irish monastery - which shows four crosses inside the round monastic wall and eight crosses outside it.
The symbol of the shamrock is from a legend about St. Patrick that says he used a shamrock with its three leaves to explain the Trinity, the triple nature of God.