Kilmacduagh Monastery is found 5 km from the town of Gort in County Galway, Ireland. It was the birthplace of the Diocese of Kilmacduagh, whose name means "church of Duagh's son". The 7th century Saint Colman, son of Duagh, established a monastery on land given him by his cousin King Guaire Aidne mac Colmáin (died 663 in Ireland) of Connacht.
The monastery contains a round tower, notable as both fine example of this particularly Irish feature but also because of its noticeable lean, over half a metre from the vertical. The tower is over 30 metres tall, with the only doorway some 7 metres above ground level.
This site was of such importance that it became the centre of a new diocese, the Diocese of Kilmacduagh, in the 12th century; it is now incorporated into the Diocese of Galway. The monastery, because of its wealth and importance, was plundered several times in the 13th century.