Ivry castle was built on a spur with access barred by a ditch whose site commands the crossing of the Eure. It has the appearance of classic arrangements with a high enclosure wall and a bailey whose chronology has not been fully established.
But the large rectangular tower which was partly buried by works beyond the summit of the spur, are probably signs of the vestiges of the older Norman stone keep. It was built under the authority of Duke Richard I, by his half-brother Raoul d'Ivry.
This is a construction of exceptional size, 28 m x 11 m, at a time - around the year one thousand when wood and earth dominated military architecture.
The remains of the walls with flat buttresses, and fishbone bonding, enable the reconstruction of a ground plan presenting a ground floor and noble floor.
The layout of the great Carolingian palatial residences can be seen - with a large reception hall, private apartments and a chapel with projecting apse - whose plan is resumed and adapted in the reinforcement of military functions in the Anjou and Anglo-Norman quadrangular keeps. The Tower of London or Falaise castle are 11th century examples.
There are textual references to towers contemporary to those of Ivry, also built under the authority of the Duke, in Rouen or Bayeux, whose remains do not survive.

Bibliography

- Pitte, Dominique. "Le château d'Ivry (Eure)". La Normandie vers l'an mil, Rouen : Société de l'histoire normande, 2000. - p. 77-83.
- Mesqui, Jean. “ Ivry-la-Bataille ”. Châteaux et fortifications en France. - Paris : Flammarion, 1997.