This fortification would have been built towards the end of the 11th century by the counts of Breteuil and controlled the road crossing of the river.
In 1119, Henry I Beauclerc besieged the castle which had just been enlarged by Eustache de Breteuil. In 1136, it resisted the siege laid by Thibaud de Blois, but was taken by Robert of Leicester. It was probably destroyed slightly before 1377.
All the entrenchments of the Câtelier are remarkable above all due to the exceptional state of conservation of the earthworks elevations.
The main structure is an elliptical wall 100 m by 70 m, surrounded by ditches twenty or so metres wide and a dozen metres deep, preceded by a an embankment.
On the inside a rectangular cavity can still be discerned (which was perhaps a building) and, above all, at the southernmost extremity, a motte joined to the embankment, at the top of which can still be seen the vestiges of a flint tower, which may have been quadrangular.
At the south of the enclosure, there are other embankments and ditches belonging to elements of the entrenchments part of which disappeared in the 19th century.

Bibliography

- Fallue L., Histoire du château de Radepont et de l’abbaye de Fontaine-Guérard, Rouen, 1851, p. 32.
- Delisle L. et Passy L. éd., Mémoires et notes de M. Auguste Le Prévost pour servir à l’histoire du département de l’Eure, t. II, Evreux, 1864, p. 594-595.
- Coutil L., Archéologie gauloise, gallo-romaine, franque et carolingienne (département de l’Eure). I. Arrondissement des Andelys, Paris-Evreux, 1895, p. 72 et 130-131.
- Doranlo R., Camps, enceintes, mottes et fortifications antiques du département de l’Eure, Bulletin de la Société des Antiquaires de Normandie, 1919-1920, 34, p. 164.