The city was built by II Antiokos in the name of his wife in between the years of 261 - 246 B.C and called as "Laodecia". Hellenistic time began with Alexander the great in 334 BC and after his death, one of his generals, Selekos I ruled the area for twenty years then the province became the part of the Pergamene kingdom and in 129 BC the city, especially Hierapolis and Laodicea became two important cities of the Roman province of Asia. Laodicea became the rich city as the banking center and the city of purple dye with eye solve and Hierapolis became the spa center for Roman troops and aristocrat families. Rome also made big highways for safe trade.
After the Roman Empire was split into two at the end of the 4th C AD, the area was ruled by the Eastern Roman empire called Byzantine and the glory was ended up in 7th and 8th centuries as the less populated small town. Arab raids began in 9th and 10th centuries. In 1040, Turkoman troops took over the city just after the Dandanakan battlefield and Turkish era began. Denizli and its surroundings changed hands between the Turks and the Byzantines until the end of the 12th century and finally when Seljuk Sultan Kaykhusraw I took over the throne of Selçuk Empire in 1207, passed into the hands of the Turks again. The Sultan permitted to settle about 200.000 Turkmen tents of the Nomadic Turcoman families down in and around the city.
In Ottoman period was in 1360 first but Tamir Lenk destroyed the Ottoman state at the battle of Ankara in 1402 and, as a result, the town was given back to Germiyanoglu principality. In 1429, the whole Germiyan land with Denizli passed into the hands of the Ottomans. The city had a chance to get developed in Ottoman period in 15th C AD due to the famous Turkish guilds founder called Ahi Evran came to Denizli and established a big guilds association here. Buldan has become the famous textile town for Ottoman Janissary troops as to make military uniforms and nice clothes and fabrics in looms and workbences have produced Buldan clothes for concibunes and Queen mothers for centuries. Denizli divided into three major states under Ottoman rule till 1920 and it became a province as Denizli in 1923 when Turkey was proclaimed as a new country.
The old city is 6 km north of the modern city and was built by Antiokos and named Laodicea after his wife. This city is mentioned in the Book of Revelations as one of the seven churches. The nearby city of Triopolis was known as the center of bishops. Hierapolis, also called Pamukkale, is another historical city which is marked by its stalactites, cataracts and basins and offers a stunning spectacle.
Among the historical ruins, the most prominent are the Roman and the Byzantine ruins, which are better preserved than others. Later the Muslims - Seljuks and Ottomans - introduced the beauty of Islamic architecture to Denizli.