The Mouse Tower (Mäuseturm) is a stone tower on a small island in the Rhine. The Romans were the first to build a structure on this site. It later became part of Franconia, and it fell and had to be rebuilt many times. Hatto II, the Archbishop of Mainz, restored the tower in 968. The story of how it came to be called the 'Mouse Tower' comes from a folk tale (Hatto was being eaten alive by mice in a tower). In 1298 the structure became an official customs collection tower. It was destroyed by a French army in 1689, then rebuilt in 1855 as a Prussian signal tower.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.