St Patrick's Roman Catholic Cathedral stands proud on one of Armagh's hills looking across at the more ancient St Patrick's Church of Ireland Cathedral. This towering Gothic structure, which is the centre of the Roman Catholic Church in Ireland, was designed by the architect Thomas J. Duff, who had previously designed Newry Cathedral, and was begun in 1840. However work stopped for many years during the Famine, and only resumed on the cathedral again in 1854. The building was finally completed and dedicated in 1873. The walls of the vast interior are decorated with elaborate mosaics and the centerpiece of the cathedral is a huge sculpture of wings that replaces the traditional altar. The enormous Grand Organ, first installed in 1875, has been restored to its former glory.