This antique city situated in the Pamukkale region is 22 km from Denizli . It is also known for its thermal springs. It is known to have been established by Eumenes II, King of Pergammon, during the 2nd century and its name to have been taken from the wife of Telephos, Hyera, who established Pergammon. The city was the capital of Phrygia during the reign of Constantin the Great, and later become the bishops center during the Byzantine Period.
Roman architecture dominates the city.