The Greek theatre of Syracuse lies on the south slopes of the Temenite hill, overlooking the modern city of Syracuse. It was first built in the 5th century BC, rebuilt in the 3rd century BC and renovated again in the Roman period. Today, it is a part of the Unesco World Heritage Site of 'Syracuse and the Rocky Necropolis of Pantalica'.
It seems that the theatre was renovated in the third century, transforming it into the form seen today. Its structure was extended, taking into account the shape of the Temenite hill and the best possibilities for acoustics. Another typical characteristic of Greek theatres is the celebration of the panoramic view, also applied to the theatre of Syracuse, offering a view of the bay of the port and the island of Ortygia.
During the Roman era, important modifications were made to the theatre, perhaps at the time when the colonia was founded in the early Augustan period. The cavea was modified to a semicircular form, typical of Roman theatres, rather than the horseshoe used in Greek theatres and corridors allowing access past the scene building (parodoi). The scene building itself was reconstructed in monumental form with rectangular niches at centre and two niches with a semicircular plan on the sides, containing doors to the scene.
References:The Roman Theatre of Mérida is a construction promoted by the consul Vipsanius Agrippa in the Roman city of Emerita Augusta, capital of Lusitania (current Mérida). It was constructed in the years 16 to 15 BCE. One of the most famous and visited landmarks in Spain, the Roman Theatre of Mérida is regarded as a Spanish cultural icon and was chosen as one of the 12 Treasures of Spain.
The theatre has undergone several renovations, notably at the end of the 1st century or early 2nd century CE (possibly during the reign of Emperor Trajan), when the current facade of the scaenae frons was erected, and another in the time of Constantine I (between 330 and 340), which introduced new decorative-architectural elements and a walkway around the monument. Following the theatre"s abandonment in Late Antiquity, it was slowly covered with earth, with only the upper tiers of seats (summa cavea) remaining visible.