Letoon was the sacred cult centre of Lycia, dedicated to the goddess Leto. According to legend, Leto was loved by Zeus. She was chased away by the jealous Hera, but  gave birth to twins (Apollo and Artemis) on the island of Delos.  Another legend gives the birthplace as the source of the Xanthos River. In one story, shepherds angrily refused to let her drink from a fountain—in retaliation, she turned them into frogs.

The remains of two temples on the hillside, decorated with Doric friezes, date back to the 4th century B.C. The remains of the theatre can also be seen. The Byzantine church and Roman Nymphaeum are worth visiting.

Like other Lycian cities, Letoon was ravaged by Arab raids. The area started to silt up with sand brought down by the Xanthos River.