St Stephen's Cathedral, with its 450feet high spire, is not only the main sight and emblem of Vienna; it is also the city's most imperative Gothic structure and has been the cathedral church of the archbishopric since 1722. The church reflects the never ending labors of generations since the 12th C. and represents eight centuries of architectural history. The unique Romanesque church was replaced by a Late Romanesque one in the 13th C. All that relics of it are the colossal gate and the "Heidentürme". The choir, and the Chapels of St Eligius, St Tirna and St Catherine were accomplished in that same century, while the south tower, the nave and the Chapel of St Barbara was completed in 15th C.