High Quality Content by WIKIPEDIA articles Christ Church Cathedral (or, more formally, The Cathedral of the Holy Trinity) is the cathedral of the United Dioceses of Dublin and Glendalough and the cathedral of the Ecclesiastical province of the United Provinces of Dublin and Cashel in the Church of Ireland. It is situated in Dublin, Ireland and is the elder of the capital city's two medi val cathedrals, the other being St Patrick's Cathedral.