Chios (; , ;  alternative transliterations Khíos and Híos) is the fifth largest of the Greek islands, situated in the Aegean Sea, off the Anatolian coast. The island is separated from Turkey by the Çesme Strait. Chios is notable for its exports of mastic gum  and its nickname is The mastic island. Tourist attractions include its medieval villages and the 11th-century monastery of Nea Moni, a UNESCO World Heritage Site.