St Mary's Cathedral in Killarney, designed by the architect Augustus Pugin, is tonight celebrating the 150th anniversary of its consecration.
Considered Pugin's favourite project and one of the finest neo-Gothic cathedrals in Europe, St Mary's was conceived after Catholic emancipation in 1829.
The diocese of Kerry, which includes parts of north and west Cork, had been without a cathedral for 200 years.
Construction was interrupted by the Great Famine, when the unfinished building became a shelter for the sick and dying.There are famine memorials and graves in the grounds of the cathedral.
Over the past year, the 85-metre (280ft) spire has been repaired and new paving laid. Large plasma screens have also been set high over the aisles to allow Mass-goers a fuller view of the altar and a loop sound system for the hard of hearing is being installed in the €1 million works.