Fort Lupin, also known as Fort de la Charente, is an artillery battery in Saint-Nazaire-sur-Charente, in the department of Charente-Maritime. It was built in the 1680s to a design by Sébastien Le Prestre de Vauban, and it is now in good condition.
The fort consists of a semi-circular gun battery ringed by a parapet with twenty-two embrasures. A tour-réduit and two blockhouses are located at the gorge. The fort is further protected by a ditch, a covertway and a glacis.
Fort Lupin was never attacked, and it never fired its guns in anger. It was decommissioned in the late 19th century, and was subsequently abandoned and vandalized.
The fort was sold to a private owner in 1964. The owners have restored the fort, and today it is in good condition. It is not open to the public on a regular basis.
References:Sigmaringen Castle was first mentioned in the year 1077 in the chronicles of Petershausen monastery. The oldest parts of the castle are concealed beneath the alterations made during the 17th and the 19th centuries. The secret of the earliest settlement built on this defendable rock will never be fully revealed: large-scale excavation work would be necessary, which the extensive land development renders impossible. Judging from the many Roman remains unearthed in the area around Sigmaringen, the 12th century keep known as the 'Roman Tower' could be traced back to a Roman predecessor.
The castle remains that have been preserved (gate, great hall and keep) date back to the Staufer period around 1200. The castle remains were integrated into subsequent buildings. The foundations of the castle buildings are to a large extent identical to the surrounding castle wall.
These remains give us a good idea of how the castle might have looked during the 12th century.