At the bottom of the valley between the village houses and the river Mauldre, sleep the remains of an ancient castle. It is surrounded by a ditch twenty to thirty meters wide with a depth of 4 meters, which had been dug for his defense.
The medieval castle of Beynes is a perfect example of these fortresses born of feudalism, in the context of struggles against the Capetian expansion. But he kept a strategic value to the end of the Middle Ages, primarily because of the Hundred Years War and the wars of religion, particularly virulent in western Paris.
Castle Beynes is mentioned for the first time in one of these tributes made to 3rd 1176 by Simon de Montfort, said the Bald, Count of Evreux and lord of Montfort.
The Counts of Brienne showed little to this land away from their fields and sold it to the chancellor Poyet. During his disgrace in 1542, Francis gave his property to the first of Pisseleu Anne, Duchess of Etampes.
At the death of Anne of Pisseleu, Henry gave the second Beynes to Diane de Poitiers in 1556. She died in 1566, leaving his daughter Beynes Francoise de Breze, widow of the Duke of Bouillon. The heiress of the latter was his daughter, Diane de la Marck, a widow in 1564, and the Duke of Nemours in 1573 by Henri de Clermont, Count of Talard. In 1596, she was married to Jean Babou, Earl of Sagonne, with whom she was at the Chateau of Beynes, December 26, 1587. The Countess remained Sagonne Beynes lady, until 1622. His heir was Henry of Clermont, Comte de Tonnerre, second son of the husband who is quick to sell Beynes.
