Facades:

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Left: Saint-Sernin, Toulouse
- Right: Amiens Cathedral
Comparisons:
Sant' Ambrogio, Milan
Italian Romanesque, late 11th century
Saint-Etienne, Caen
French Romanesque, begun 1067
Abbey of St. Denis
French Early Gothic, 1140 (Royal Portal and Stained Glass)
Chartres Cathedral (Notre-Dame)
French Gothic, facade 1145-1170
Paris Cathedral (Notre-Dame)
French Gothic, begun 1163
Orvieto Cathedral
Italian Gothic, begun 1310
Milan Cathedral
Italian Gothic, begun 1368