ISHTIB, or Istib (anc. Astibon, Slav. Shtipliye or Shtip), a town of Macedonia, European Turkey, in the vilayet of Kossovo; 45 m. E.S.E. of Uskub. Pop. (1905) about 10,000. Ishtib is built on a hill at the confluence of the small river Ishtib with the Bregalnitza, a tributary of the Vardar. It has a thriving agricultural trade, and possesses several fine mosques, a number of fountains and a large bazaar. A hill on the north-west is crowned by the ruins of an old castle.