Castle of Verneuil-sur-Avre, Medieval castle in Verneuil d'Avre et d'Iton, France

The castle of Verneuil-sur-Avre is a ruined 12th-century fortress of which only the keep, the Tour Grise, remains. This curved-plan tower stands on the rampart at the southern edge of town, by the Avre. Built of ferruginous puddingstone, it is 35 metres high with walls 4 metres thick; its top was rebuilt in the 19th century. The castle itself has left no standing remains.

The fortress was founded around 1120 by Henry I Beauclerc, making Verneuil a major stronghold in Normandy. Later, after the annexation of Normandy, King Philip II had the famous Grey Tower built to monitor the region and maintain control.

The tower's name, the Grey Tower, comes from the ferruginous puddingstone used to build it. It had two doors, one facing the town and one facing the ramparts, and chroniclers called it "moult forte et imprenable" as long as there was food inside. It often served as the last refuge for the town's defenders.

The fortress is accessible from the outside, allowing visitors to explore the medieval structure and its surroundings. The site with its towers and moat offers varied perspectives and angles for viewing and photographing the fortification.

The king granted municipal freedoms to the town's people even though the new fortress served primarily to watch over the region. This unusual combination of military oversight and civic rights shows a rare balance between authority and trust.