Abbaye de Montebourg, Romanesque abbey in Montebourg, France.

The Abbaye de Montebourg is a former Benedictine monastery rebuilt between 1892 and 1933, now housing a private college and an agricultural high school. Its light tan stone buildings stand behind a low stone wall with a metal gate; the main facade has two rows of windows and slightly projecting gabled sections, a steep dark grey roof with a small square bell tower and a short spire, and a cylindrical stone tower with a conical roof to the right.

Founded by William the Conqueror between 1066 and 1087, the Benedictine monastery had no surviving foundation charter, so its exact origins remain unclear. Henry I granted its patronage to Richard de Reviers between 1100 and 1107, and gifts from Anglo-Norman kings and Rouen's bishops multiplied until the 1180s. The abbey passed into the royal domain in 1204 when Philip Augustus took Normandy; the buildings visible today were rebuilt from 1892 to 1933.

The abbey's name, Notre-Dame de l'Étoile, comes from the 15th-century foundation legend: the monk Roger dreamed that a star fell on the hill, and the Virgin told him to build an oratory there. Montebourg's inhabitants are still called Cassins, after the monks who came from Monte Cassino. The monks held the right to present parish priests of the Cotentin to the bishop of Coutances.

Visitors can examine the medieval stonework and architectural details throughout the grounds at their own pace. Plan time to walk around and observe how the various structures fit together and display the craftsmanship of the period.

The name Montebourg comes from the Latin Mons Burgi, and locals are still called Cassins after the monks' legendary origin at Monte Cassino. The abbey's cartulary, a record of its lands and revenues, is kept today in the Manuscripts Department of the Bibliothèque nationale de France. The community held property as far as Devon, Dorset, Berkshire and the Isle of Wight.