Ostrvica or Ostrovica (Turkish: Sivrice Hisar) was a small fortified town built on one of the peaks of Rudnik mountain, 4 kilometres (2.5 mi) northwest of the town of Rudnik.[2] After 1323/1324, when it was recorded for the first time, it belonged to the Kingdom of Serbia, Serbian Empire, Moravian Serbia, Serbian Despotate and Ottoman Empire. In 1451 the Ottomans razed it to the ground.