This photograph, taken by Charles-François Bossu, known as Marville, in August 1862, shows the beginning of the restoration work on the château, led by Eugène Millet. In a first-floor window we can see workers. On the left of the photograph, we can see the museum’s four floors. On the museum’s ground floor were large casts; on the mezzanine, inscriptions; on the first floor, the rooms dedicated to prehistory and the Gallic Wars; and on the second floor, the lacustrine and Gallic collections.