Iasos – Kıyıkışlacık 37°16′48″N 27°35′06″E – Italian excavations Levi

Iasos or Iassos (; Greek: Ἰασός Iasós or Ἰασσός Iassós), also in Latinized form Iasus or Iassus (), was a Greek city in ancient Caria located on the Gulf of Iasos (now called the Gulf of Güllük), opposite the modern town of Güllük, Turkey. It was originally on an island, but is now connected to the mainland. It is located in the Milas district of Muğla Province, Turkey, near the Alevi village of Kıyıkışlacık, about 31 km from the center of Milas.