Qashliq, also known as Sibir, was a Siberian Tatar fortress in present-day Tyumen Oblast, Russia which served as the capital of the Khanate of Sibir during the 16th century. Located on the right bank of the Irtysh River, 10.5 miles from the modern city of Tobolsk, Qashliq was first mentioned in the 14th century. In 1582, Qashliq was destroyed by Yermak Timofeyevich's Cossack expedition at the Battle of Chuvash Cape during the Russian conquest of Siberia, and it was briefly retaken by the Tatars in 1584 before being lost forever in 1586. Tobolsk was founded in 1587, replacing Qashliq as the population center of the region.