Porta Praetoria, a gateway to the city of Regensburg, dates from 179 AD. Among Porta Nigra in Trier, it is the only remaining Roman gate north of the Alps. Giant blocks of stone were used to construct this gate in the northern wall of the Roman military camp. It survives as a reminder of Castra Regina, the Roman settlement.
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.