The Cathedral of Saint Charles Borromeo is a Roman Catholic cathedral church in Saint-Étienne, France. It has been the seat of the Bishop of Saint-Étienne since the foundation of the diocese. The church, dedicated to Saint Charles Borromeo, was constructed in a primitive neo-Gothic style, on a Latin cross groundplan with transept and triple nave, and a belltower on the west front. The building was however an excessively ambitious one right from the start, and remains unfinished: it was intended that there should be another three belltowers and a dome, besides quantities of external and internal decoration presently lacking.