A service of the Conseil Général of the Departement of Orne, situated in Alençon, France. The service brings together the departementa and the 'Conservatoire des antiquités et objets d'art de l'Orne'.
More information on the French Wikipedia page [1].
The website, in French, is [2]
There is also the Société historique et archéologique de l'Orne - French Wikipedia page [3]: website, in French, [4].