Carndonagh has always been a very important ecclesiastical site dating back to the 5th century. The town is dominated by the church of the Sacred Heart and the Church of Ireland stands on the site of a church founded by Saint Patrick.

The church bell is believed to have come from the ‘Trinidad Valencera’, the Spanish Armada Ship wrecked off Kinagoe Bay in 1588. The town also has an early Christian cross, the Donagh Cross, dating from the 7th century which stands 11 feet 6 inches high.