Exceptional opening of the Parc de la Sous-Préfecture with the discovery of the fortifications and the medieval castle of Saint-Dizier.

In the second half of the 11th century, the family of lords of Dampierre created a fortified town at the confluence of the Marne and the Ornel. A city organized around a castle and fortifications flanked by a dozen towers. Over the centuries, it became a place of protection for the inhabitants and illustrious figures. Henri IV, Marie Stuart… After the Second World War, the castle houses the Sub-Prefecture.