The ruins of Hierapolis (Holy City) are the other main attraction when you come to Pamukkale. The city was founded in 190 B.C. by Eumenes II, king of Pergamon. In the 2nd and 3rd centuries, it reached the height of its development as a Roman thermal bath center.

Hierapolis has such extensive ruins which is suggested: the city walls, the octagonal Martyrium of St. Philip, the 2nd century theater, Temple of Apollo, basilica, then the necropolis which covers 2 km². and contains some of the best examples of tomb styles; it is one of the best-preserved ancient cemeteries in all of Anatolia.

Dating back to the Calcholithic age, this was the site of a settlement of the earliest communities, and changed hands continuously, becoming the center of various civilizations in different time periods. The ancient city of Laodikeia is close here, within the borders of Denizli, with its ruins awaiting for the sightseers. In addition to Triopolis which was known as the center of bishops, while Christianity spread. Hierapolis is another Ancient City, being a real historical treasure, while it also offers a real wonder of nature in its vicinity.

In the Antiquity, Eumenes 11, King of Pergamum, who rebuilt Hierapolis after its destruction by an earthquake, used to like bathing in the healing waters of the springs there, in a manner that planted the seed of the following concept in the soils of the Aegean lands that has survived up until now: The power lives in great splendor. Between the first and fourth centuries, Hierapolis was a city popular with its spas in the Roman Empire. Many queens had beauty baths in the red colored healing thermal waters of the Roman baths with soaps scented with bay leaves and, refreshed, they presented themselves to the Caesars with stalks of grapes.

Christianity started to spread in this area in the 1st century AD. Since St. Philip, one of the twelve apostles, was killed here, Hierapolis became a sacred place for the Christians. In 394 it came under the control of the Byzantine Empire and became a center of Bishopric. However, when the Turks came to the area, they wanted to conquer the city and because of continuous wars between the Turks and the Byzantine, the city became a battlefield. Eventually the city grew weaker and weaker until a big earthquake brought an end to its history in the XIII Century.

Between the fifth and twelfth centuries, Hierapolis was a center of religion for the Byzantines. The white frozen masses of travertine formed by warm waters up to 35 degrees that gush from the springs, soon they were circled with churches and cemeteries. Missioners came to baptize themselves and their deads in the holy waters of sanctified springs.

This is a UNESCO World Heritage site.