The Castle of Trezzo sull'Adda is located on a hill within a bend of the Adda river and from this protected on two sides. On the remaining side it is closed by a wall and a 42-meter high tower. Part of the castle was the fortified bridge over the river, destroyed in 1416.
The site was inhabited since prehistoric time by Celtic populations and after the VII century hosted a Longobard settlement, which was also at the origin of the first fortification on the hill. In 1370 Bernabò Visconti, lord of Milan, ordered the construction of a new caste, which was built on the remains of the previous fortress and completed in 1377.References:
Bouillon Castle was mentioned first in 988, but there has been a castle on the same site for a much longer time. The castle is situated on a rocky spur of land within a sharp bend of the Semois River.
In 1082, Bouillon Castle was inherited by Godfrey of Bouillon, who sold it to Otbert, Bishop of Liège in order to finance the First Crusade. The castle was later fitted for heavy artillery by Vauban, Louis XIV's military architect in the late 17th century.
The castle is entered over three drawbridges. The main courtyard then leads to the ducal palace with its 13th century Salle Godefroy de Bouillon. From there visitors climb up to the top of the 16th century Tour d’Autriche for a breathtaking panorama of the town and river, before they way back via the torture chamber, citerns and dungeons, and past the 65m deep well Shaft.