Halicarnassus (Greek: Halikarnassós or Αλικαρνασσός Alikarnassós; modern Bodrum), an ancient Greek city on the southwest coast of Caria, Asia Minor, on a picturesque, advantageous site on the Ceramic Gulf (Gulf of Cos, Gulf of Gökova). It originally occupied only the small island of Zephyria close to the shore, now occupied by the great castle of St. Peter, built by the Knights of Rhodes in 1404; but in course of time this island was united to the mainland and the city extended so as to incorporate Salmacis, an older town of the Leleges and Carians.