Aghadoe Cathedral

Aghadoe Cathedral was a church that may have been the seat of a bishop at Aghadoe, Ireland (later joined with the Bishopric of Ardfert). The now ruined cathedral overlooks the Lakes of Killarney from Aghadoe, a few miles from Killarney. Aghadoe may have been the site of a church as early as the seventh century, but extant remains are of a stone structure built in the eleventh and twelfth centuries.

Aghadoe, (Irish: Achadh Deo "place with two yews") may have begun as a pagan religious site. The site has also been associated with the fifth century missionary St. Abban, but seventh century ogham stones mark the first clear evidence of Aghadoe being used as an important site. According to legend, St. Finian founded a monastery at Aghadoe in the sixth or seventh century. The first written record of a monastery dates from 939 AD in the Annals of Innisfallen where the Aghadoe monastery is referred to as the "Old Abbey." The monastery at Aghadoe had a close relationship with the one on nearby Innisfallen Island. Maelsuthain O'Carroll, one of Innisfallen's greatest scholars, was buried at Aghadoe after his death in 1010 AD, and a legend suggests that the two monasteries were connected by a causeway across Loch Lein. In 1027 the Annals make the first reference to a stone building on the site, noting the construction of Damh Liag Maenig (Maenach’s house of stone). Construction on the round tower began the same year. Aghadoe witnessed the turbulence of the times. In 1061, an O'Cathail, the heir to the local dynasty of Eóganacht Locha Léin, was taken from the church and murdered.

In the middle of the twelfth century Amhlaoibh Mór Ó Donoghue, the leader of the Ó Donoghue—the new rulers of Eóganacht Locha Léin, had a new church building, later called the "Great Church," constructed in the Romanesque style and dedicated to the Holy Trinity. The new structure, completed in 1158, incorporated part of the old stone building in its northwest section and makes up the western section of the extant remains. When Amhlaoibh Mór Ó Donoghue was killed, his body was carried to Aghadoe and interred in the church. The final addition to the church was constructed in the twelfth century. The addition served as a chancel or choir, and was later separated from the rest of the church by a wall.

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