This street extending from the baths to the Theatre is called the Arcadian Street. Originally built in the late Hellenistic Period, the street was restored during the reign of the Emperor Arcadius (395-408 AD.), from whom it takes its present name. There were galleries and shops all along either side of the street, which is 530 metres long and 11 metres wide. In the centre section is a structure containing four high columns, an element of decoration which was constructed in the 6th century AD. Along either side were gates in the form of monumental arches. Since this street extended to the harbour, it was also referred to as "Harbour Street".
This theatre, which had a seating capacity of 25,000 was first constructed during the Hellenistic period, although the present structure dates from the 1-2nd centuries AD. The Roman Theatre was begun during the reign of Claudius (34-41 A.D.), and it took 60 years to build. The second and third storeys of the skene (25x40 m) were constructed during the reigns of the emperors Nero (54-68 A.D.) and Septimus Severus ( 193-211 AD.). Only parts of the skene now date from the Hellenistic period. The Theatre has three cavea, each 22 rows, to which access was obtained via flights of steps between the cavea. The skene is 18 m. in height and the inner facade was ornamented with reliefs, columns, blind niches, windows and decorated with statues on three levels. The semicircular orchestra, surrounded by a channel, fronted a second skene supported on columns, 2.70 metres in height, which was approached by flights of steps. This section of the skene was used during the Roman period.