The private library or bibliothéque of the Château de Groussay located in Montfort-l'Amaury, France. The Château was built in 1815 by the duchesse de Charest, a daughter of Louise Elisabeth de Croÿ-Havré, marquise de Tourzel, the governess of the royal enfants de France of Louis XVI and Marie Antoinette.
The desk is especially wonderful, isn't it? I'd love to have a similar one with a much deeper horizontal working surface so I could pile up more books.