Photo : Johann Dréo (User:Nojhan) / Wikimedia Commons (CC BY-SA 3.0)
The castle of Château-Thierry, in the Aisne, occupies a rocky spur above the Marne. It controlled this navigable river, vital to the region's economy, as well as the old Roman road from Soissons to Troyes.
The town that grew up around the stronghold was coveted many times during its long history, up to the last German offensives of the First World War.
A private, lived-in château on the Champagne route, with 17th- and 18th-century décor by Watteau, Boucher and Oudry.
Of the old 13th-century castle of Fère-en-Tardenois, on an artificial mound, the bases of its seven towers survive.
The castle of La Ferté-Milon looks like a romantic stage set: its broad façade, 104 m wide and 20 m high, opens onto nothing.
An early 16th-century brick château, considered the oldest of the many manor houses in the Villers-Cotterêts area.
A few kilometres from Soissons, the village of Septmonts is known above all for its keep, an impressive remnant of the bishops of Soissons' residence.
A remarkable 14th-century keep 45 metres high, the former pleasure residence of the bishops of Soissons.