East of the present museum is a Christian basilica consisting of a nave and two aisles. It dates from the 6th century AD. Walking along the route of the Plateia (which now passes through the modern swimming pool) reminds us that this main street dividing the ancient city was once decorated with colonnades, porticos, and important buildings located on either side. The street runs directly toward the city walls passing through a gateway built in Byzantine times atop an earlier fountain. On the way is a basilical structure with two aisles and a nave whose eastern end terminates in an apse. The city walls were built in 396 AD. and were reinforced by 28 towers. Passing through Byzantinegate you come to a rather well preserved section of the Plateia. This part was built during the reign of Domitian (81-96 AD.) and terminates with the Arch of Domitian. This monumental gateway was actually erected by Julius Frontinus, who was proconsul of the Roman province of Asia (middle western Anatolia) in 82 and 83 AD., and dedicated to the emperor. The gate has two round towers and three portals. Excavations are now in progress to reveal the remains of shops and houses that once lined both sides of this street.
Northeast of the street between the Byzantine and Domitian gates was the agora (market) of ancient Hierapolis. The traces of the city's original theater may be seen above. If you follow the road in the direction of the necropolis you pass by the imposing walls of a building originally erected as baths around the end of the 2nd century AD. It was converted to a church in the 5th century. The huge necropolis of Hierapolis, largest ancient graveyard in Anatolia with more than 1200 tombs, spreads out on either side of the road for a distance of two kilometers. It contains tumuli, sarcophagi, and house-shaped tombs that range in date from the late Hellenistic period to early Christian times. It is one of the most extensive and best preserved ancient cemeteries in Anatolia. The road proceeds on to the hot springs of Karahayit located 4 kilometers away.