Fort Constantin or Fort Grand Duke Constantine (Fort Großfürst Konstantin) is a historical fortress in Koblenz-Karthause district of Koblenz, Germany, built in 1827/1828. It was part of the Prussian fortress system of Koblenz and Ehrenbreitstein. It was named after the Grand Duke Konstantin Pavlovich of Russia.
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.