Built in 333 BC along Gela's western coastline at Capo Soprano by the tyrant of Syracuse, Timoleon, Gela's ancient Greek fortifications are remarkably well preserved, most likely the result of being covered by sand dunes for thousands of years before their discovery in 1948. The 8m-high walls were originally built to prevent huge amounts of sand being blown into the city by the blustery sea wind. Today authorities have planted trees to act as a buffer against the encroaching sand.
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.