The Lombardian city of Bergamo is composed of two parts, Città Alta (Upper Town), built up on the hills, and the Città Bassa (Lower Town), which is a lively financial, industrial and administrative centre of national importance.
A milestone in the history of Bergamo was its incorporation into the Venetian State in 1428, which lasted for over three centuries and a half. The two parts of city are separated, both physically and symbolically, by the powerful Venetian Walls, which were built by the Serenissima Republic of Venice in the second half of the 16th century to defend the city, which was the farthermost centre on the Mainland, close to the border with Milan's territory.
The walls never underwent any siege. That is why they remained almost intact to the present day. The system consist of 14 bastions, 2 platforms, 100 embrasures for cannons, 2 armouries, four gates, not to mention the underground structures featuring sallies, passages and tunnels.
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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.