The Catholic Cathedral of Kilmore is relatively new. The architect was Ralph Byrne and it is built of Granite with Limestone and Portland Stone details by Sisk Brothers, Cork. It has five bays and is two storeys high. The spire stands at 224ft above Farnham Street and is topped with a gilded cross. The first Catholic Church was built in 1823 on the same site and the land was supplied by the fourth Baron Farnham. In 1843 Bishop James Brown of Kilmore moved the seat of the Bishopric from Cootehill to Cavan.
In 1862 renovation was carried out to Cavan Church and it was raised to the status of Cathedral. In the later part of the 19th century it owned some truly fine church furniture. Pews were reserved for Cavan’s more important citizens. In 1919 a decision was made to build a bigger cathedral on the site behind the old one. The old cathedral was taken down carefully and rebuilt in Ballyhaise where it still stands. Bishop Finnegan collected the money for the cathedral and in 1942 the building was complete but was only consecrated in 1947, when all outstanding debts were cleared. It cost £250,000. Inside the cathedral there are 18 beautiful marble columns, which were made in Carara, Northern Italy. As they were shipped during World War II, the Bishop insisted that the congregation pray for their survival on the high seas, until they arrived safely. Bishop at the time of completion was Bishop Lyons. This building has a complete set of Harvey S. Clarke stained glass windows.