Nuraghe Santu Antine, also known as 'Sa domo de su re' ('The house of the king') is an ancient megalithic edifice built by the Nuragic Civilization in Torralba, one of the largest in Sardinia. It is located in the centre of the Cabu Abbas plain. The main structure was built around the 19-18th century BC, and the other parts of the nuraghe date back to the 17th–15th century BC. The main tower originally reached a height of 23–24 metres and contains three tholoi chambers on top of each other. The central tower with diameter of 15 metres is 17 metres high. Santu Antine is made of huge basalt blocks. It has three floors. The top floor is now gone. Some 27 meters long corridors built with the corbel arch technique can be observed inside of the Nuraghe, superimposed on two floors, the Nuraghe was provided with three wells.
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.