The cessation of the construction of the new cathedral preserved a portion of the nave of the ancient cathedral from the 10th century.
The first church at this location, the ancient cathedral, likely dates back to the second half of the 10th century (late Carolingian period). It was much longer than the current building, making it one of the largest churches of that time.
Excavations beneath the current cathedral have revealed the presence of a large transept. Opinions differ on whether this transept is original or was added later. In the former case, the current Lower-Work would have been preceded by a smaller Carolingian church built in the same location. The apses of this church, with a non-projecting transept, were discovered during the excavations.
In 1225, the choir was completely destroyed. It was decided to build another cathedral slightly to the east. The construction site of the new cathedral led to the gradual destruction of the eastern part of the old one, which then became Our-Lady of la Basse-Œuvre. (Basse-Œuvre (Lower work), named as such in comparison to the new cathedral, the Haute Œuvre (Upper work)).
The west facade
The west facade originally included at least one porch, and perhaps a tower.
It underwent renovation in the 11th century following a fire. Above the window, three peculiar figures can be observed, originating from an older structure.
Interior of the Nave – 19th Century Ceramics
The current nave now comprises only three bays, compared to the nine it had in its greatest extension.
The 19th century was a flourishing period for ceramics in the Beauvaisis region, notably exemplified by Charles Lévêque’s work in 1884. One notable representation depicts the presentation of the rosary to Saint Dominic.
Access Area to the Cathedral
Remnants of three additional bays of the nave of the ancient cathedral can be found here. The arches have been reinforced to support the mass of the west wall of the cathedral.
To the left of these arches, a substantial buttress dating back to the 16th century closes off this section of the structure. Similar to its symmetrical counterpart located outside to the right, it rises significantly higher than the Basse-Œuvre.
Excavations under the Cathedral – The Old Paving
Extensive excavations have been carried out beneath the cathedral, with the most significant conducted by Émile Chani.
These excavations did not reach the apse of the old choir, which had been demolished in the 13th century during the construction of the Haute-Œuvre. (Upper Work)
The original pavement
The original pavement has been uncovered in certain areas. It is located 1.85 m lower than the current ground level.