The oldest parts of the church of Notre-Dame in Bourg-Dun date from the 11th century. It probably succeeded an abbey church which was destroyed by the Scandinavian invasions. It has vast dimensions (45 metres long), and presents a Latin cross ground plan with side aisles for the nave and choir.
The north crossing of the transept, the north side of the nave and the first bays of the choir are the only remains of the 11th century. Given the stone used, travertine, which is not well-suited for moulding work, the decoration remains austere and is confined to blind arch friezes on the upper level of the north wing of the transept and the lower level of the north side aisle of the choir. The nave, with its side aisles, was transformed at the end of the 12th century to a style already showing signs of gothic influences. The other modifications are later than the Romanesque period.
- Musset, Lucien. - Normandie romane, 2, Haute-Normandie, Zodiaque, 1974, p. 24.
- Musset, Lucien. “ Le Bourg-Dun ”, Dictionnaire des églises de France, Normandie, IV B, Paris : Laffont, 1968.