The Cité Royale de Loches is one of the best-preserved medieval fortified complexes in France. It stretches across the hilltop for nearly a kilometre and contains three distinct structures built across different centuries: the 11th-century keep (the Donjon), the 15th-century Logis Royal where the French court stayed, and the Tour Ronde. The keep alone is worth the admission — its walls are four metres thick and the views from the top take in a wide sweep of the Indre valley.
The dungeons in the Tour Ronde held some famous prisoners, including Ludovico Sforza, Duke of Milan, who covered the walls of his cell with paintings and poetry before dying there in 1508. The Logis Royal contains the tomb of Agnes Sorel, the first officially recognized royal mistress in French history, and a fine portrait of her by Jean Fouquet.