In 1927, John Bilson, an English archaeologist, put forward for the first time the hypothesis of the presence of Romanesque crypts under the gothic choir of Rouen cathedral. The parts that are currently accessible to the public were excavated by Georges Lanfry during several archaeological campaigns between 1931 and the beginning of the 1950s.
The first stage of an ambitious project to extend the cathedral towards the east, the construction of the crypts was started at the end of the 1020s by Archbishop Robert d’Evreux (†1037). The work was abandoned during the episcopacy of Mauger (1037-1055) and finally finished at the end of the 1050s or at the beginning of the 1060s during the office of Archbishop Maurille. Probably inspired from the plan of the crypt in Chartres cathedral (finished in 1027) those of Rouen were established around the central chapel situated under the high altar, the chapel which probably housed the reliquary of Our Lady mentioned in the inventory treasure house. Around the central body circulated a gallery covered with groined vaults leading into three radiating chapels. The only one completely cleared is the one in direct line to the gallery. The wells can be seen where pilgrims and believers would take holy water.
Jacques Le Maho
- Musset, Lucien. - Normandie romane, 2. Haute-Normandie, La Pierre-qui-Vire, Zodiaque, 1974, p. 32