The Keep is a historical monument from the end of the 12th century built by the Montfort family. It is also a cultural space where are proposed concerts, exhibitions, animations, escape game... You will visit the four levels of the Keep: low room, Monfort room, water tower and terrace. The current exhibition "Resources and Energies" presents four renewable resources: water, wood, aluminium and the Sun. Videos on this theme as well as on the restoration of the Keep are presented in the tank of the old water tower, transformed into a projection room. The terrace offers an exceptional view of the city of Houdan and further on, the Houdanais Country.