Hohenbaden Castle, built in 1102, and known locally as the Altes Schloss (Old Castle) was home from the 11th-15th century to the margraves of Baden. During its heyday in the 15th century, the castle had 100 rooms. In 1479 margraves moved their seat to Baden and the old castle started to decay. In 1599 it was destroyed by fire.
From the tower you have a good view over Baden-Baden and distant view of the Rhine valley. The courtyard of the ruins is also worth of seeing.References:
Sirmione castle was built near the end of the 12th century as part of a defensive network surrounding Verona. The castle was maintained and extended first as part of the Veronese protection against their rivals in Milan and later under the control of the Venetian inland empire. The massive fortress is totally surrounded by water and has an inner porch which houses a Roman and Medieval lapidary. From the drawbridge, a staircase leads to the walkways above the walls, providing a marvellous view of the harbour that once sheltered the Scaliger fleet. The doors were fitted with a variety of locking systems, including a drawbridge for horses, carriages and pedestrians, a metal grate and, more recently, double hinged doors. Venice conquered Sirmione in 1405, immediately adopting provisions to render the fortress even more secure, fortifying its outer walls and widening the harbour.
Thanks to its strategical geographical location as a border outpost, Sirmione became a crucial defence and control garrison for the ruling nobles, retaining this function until the 16th century, when its role was taken up by Peschiera del Garda.