Just outside of Ardglass, Ardtole is one of the oldest churches in the area. The ruins date back to the 1300s but the site was founded by Saint Patrick.

Ardtole Church is one of many which were in the area in the 1300s. The ruins sit atop a large hill with excellent views over the surrounding countryside. It is the last church from its era still standing but this is due to its abandonment in the 1400s.

The local people had fallen out with their chieftain over the price for cattle. When they found him asleep in a drunken stupor they tied his beard to the briers. Having to cut off the beard to free himself meant that he lost the symbol of his social standing. This left him very much aggrieved. He set out for Midnight Mass at Christmas when he knew they would be gathered in Ardtole and burned the church to the ground. Everyone inside perished and the church was left a ruin. This legend was an inspiration for Jonathan Swift in Gulliver's Travels.

For centuries the church stood untouched. A cross stone taken from here was incorporated into Saint Mary's Chapeltown in 1791. The ruins were excavated in 1914 by Francis Joseph Bigger. He found on the floor a carved bishop's hand, a key, some glass beads, and the largest collection of the oldest stained glass in Ireland! The glass contained a variety of colours ranging from intricately decorated fleur-de-lis to lotus motif to silver stain in blues, greens, reds, and ambers. The collection is held in the vault of the National Museum of Ireland.