Korasion was a Roman early Byzantine port city on the site of today's Atakent. The former harbour bay of Korasion is today almost completely overbuilt by the modern village of Atakent (formerly Susanoğlu) and only a few remains of the ancient buildings are still visible.
The mountain slopes on the now deserted natural harbour bay were already inhabited in early Roman times. The finds of middle imperial houses bear witness to this. However, the settlement had never grown together to one place, possibly the place became deserted again in the 3rd century.

At the time of the Roman emperors, the harbour was surrounded by a tower-proven, almost one metre thick city wall, of which only a few remains are still visible. To the west there were two three-nave basilicas, outside the village there were necropolises with rock tombs and free-standing sarcophagi, individual houses and an oil press. The cuboids of the city walls were removed in the 1940s to build a pier. An aqueduct led to a bath complex, of which today, between trees, rubble and rubble, there are only meagre remains.

According to an inscription on the eastern gate, the city was newly founded by Flavius Uranios, governor of the Roman province of Isauria, between 367 and 375 AD during the reign of Emperors Valentinian I, Valens and Gratian.

The place has never attained the status of a polis, but must have gained some importance in the 7th century due to numerous inscriptions found.

There are no archaeological evidence from later times. Already in the 10th century the place is described as lying in ruins.