Segesta was one of the major cities of the Elymians, one of the three indigenous peoples of Sicily. The hellenization of Segesta happened very early and had a profound effect on its people.
On a hill just outside the site of the ancient city of Segesta lies an unusually well preserved Doric temple. It is thought to have been built in the 420s BC by an Athenian architect, despite the city not having a large Greek population. The temple has six by fourteen columns on a base measuring 21 by 56 meters, on a platform three steps high. Several elements suggest that the temple was never finished. The columns have not been fluted as they normally would have been in a Doric temple and there are still bosses present in the blocks of the base (used for lifting the blocks into place but then normally removed). The temple also lacks a cella, any ornamentation, altar or deity dedication, and was never roofed over. The temple escaped destruction by the Carthaginians in the late 5th century.
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.