Q:St Columb's Cathedral - St Columb's Cathedral in the walled city of Derry Northern Ireland is the mother church of the Church of Ireland Diocese of Derry and Raphoe and the parish church of Templemore.It is dedicated to Saint Columba the Irish monk who established a Christian settlement in the area before being exiled from Ireland and introducing Christianity to Scotland and northern England. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
A:
Building