The Fort Bokar, often called Zvjezdan, is considered to be amongst the most beautiful instances of harmonious and functional fortification architecture. Built as a two-story casemate fortress by Michelozzo from 1461 to 1463, while the city walls were being reconstructed, it stands in front of the medieval wall face protruding into space almost with its whole cylindrical volume. It was conceived as the key point in the defense of the Pila Gate, the western fortified entrance of the city; and after the Minčeta Tower, it is the second key point in the defense of the western land approach to the city.
Bokar is said to be the oldest casemented fortress in Europe, which contains a small lapidary collection and numerous cannons.
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.