Solidor Tower (tour Solidor) is a strengthened keep with three linked towers, located in the estuary of the river Rance. It was built between 1369 and 1382 by John V, Duke of Brittany (i.e. Jean IV in French) to control access to the Rance at a time when the city of Saint-Malo did not recognize his authority. Over the centuries the tower lost its military interest and became a jail. It is now a museum celebrating Breton sailors exploring Cape Horn.
References:The Château du Lude is one of the many great châteaux of the Loire Valley in France. Le Lude is the most northerly château of the Loire Valley and one of the last important historic castles in France, still inhabited by the same family for the last 260 years. The château is testimony to four centuries of French architecture, as a stronghold transformed into an elegant house during the Renaissance and the 18th century. The monument is located in the valley of Le Loir. Its gardens have evolved throughout the centuries.