Giovanni II Paleologo, Marquis of Monferrato, ordered to build the current castle in Casale Monferrato and the work continued until 1357. When Casale assumed the role of capital of Monferrato's marquisate and obtained in 1474 the title of city, also the castle, seat of the court, changed its aspect following the restoration with the Marquises Guglielmo VIII (1464-1483) and Bonifacio V (1483-1494).
When Giovanni II Paleologo died, the Gonzaga of Mantova took charge of Casale. Because of the new military techniques the castle was reinforced. They strengthened the walls and the plan form was modified, becoming hexagonal (we can still see it). The towers were reinforced too and four new ravelins were added. At the beginning of the 17th century the castle returned to assume the role of seat of the court: indeed, the Dukes of Mantova, busy in frequent negotiations with Savoy, sojourned there. Later it became the principality of the Duke Carlo II Gonzaga-Nevers (1637-1665), who many times was there in vacation with all his court, giving a considerable impulse to the elite and cultural life of Casale.
With the crisis of the Gonzala's dynasty, the castle was about to face an unstoppable decline. The city fell into Savoy's hands in 1708 and the castle became a barracks.
In the middle of the 19th century Casale was fortified in preparation for a war against Austria and the castle became a defensive structure. The state of Savoy decided to demolish the eastern ravelin, which pointed towards the city allowing the creation of an extended public area (today's piazza Castello). The municipality designated this area as an open-air market zone. With the advent of the Unity of Italy the other three ravelins were demolished too, because they were unnecessary.
References:The ancient Argos Theater was built in 320 BC. and is located in Argos, Greece against Larissa Hill. Nearby from this site is Agora, Roman Odeon, and the Baths of Argos. The theater is one of the largest architectural developments in Greece and was renovated in ca 120 AD.
The Hellenistic theater at Argos is cut into the hillside of the Larisa, with 90 steps up a steep incline, forming a narrow rectilinear cavea. Among the largest theaters in Greece, it held about 20,000 spectators and is divided by two landings into three horizontal sections. Staircases further divide the cavea into four cunei, corresponding to the tribes of Argos A high wall was erected to prevent unauthorized access into the theatron and may have helped the acoustics, but it is said the sound quality is still very good today.
Around 120 CE, both theaters were renovated in the Roman style.