Athyras (Ancient Greek: Ἀθύρας) was a Greek[1][2] city in ancient Thrace, located in the region of the Propontis.
Its site has been located near the modern Turkish city of Büyükçekmece.[3][4]
Under the name Athyra, it is a titular see of both the Eastern Orthodox Church and Roman Catholic Church.[5][6]
41°02′02″N 28°35′24″E / 41.034016°N 28.589971°E