It is near Kumluova Village at 65th km of Fethiye – Kas highway. In accordance with a story told by the poet Ovidius, the city was established in the name of Leto, who became pregnant from Zeus. The traces of old settlement in the city goes back to 7th century BC. The ruins and the inscriptions obtained show that this place was a religious and political area. There are three temples at the center of the ruin place side by side. The one at the most northern direction is devoted to Leto, the one in the middle is devoted to Artemis and the one in the south is devoted to Apollo. In the southwest of the temples, there is a fountain building and just beside it, there is a church. In the northern side of the city, there is a Stoa and a theater, which gives its rear side to the natural slope partially, belonging to the Hellenistic Period. Letoon has been left in the 7th century AD.