The Notre-Dame d'Alençon basilica is an example of Gothic religious architecture whose construction was initiated by Charles III in the 14th century (1356) and completed in the 19th century. It has elements of Flamboyant Gothic style such as its five-bay nave or its porch. Its bell tower was rebuilt in the middle of the 18th century following a fire. The lantern above it was designed around 1736 by the engineer and architect Jean-Rodolphe Perronet, the founder and first director of the École Nationale des Ponts et Chaussées (National School of Bridges and Roads).