The Timok Valley (; ; ) is a geographical region in east-central Serbia around the Timok River. The Timok Valley corresponds to parts of two Serbian districts (Bor and Zaječar), with a total 2002 census population of 284,112. Name The Serbian name is derived from the hydronym Timok and krajina ("frontier, march"), named such due to its location and history as a borderland. It was introduced in the Interwar period as denoting the Timok confluence with the Negotin Valley and Ključ, which are part of the Timok Valley. The term has no historical or geographical basis. In Romanian, the term "Timoc Valley" () is used for the area inhabited by the Timok Romanians. "Tribalia" is also used in Romanian. The region was sometimes known as Podunavia in Medieval times. Geography The Timok Valley roughly corresponds to the Bor and Zaječar districts of Serbia. It includes six municipalities and two cities: Zaječar – 66,000 Bor – 44,000 Negotin – 37,000 Knjaževac – 32,000 Sokobanja – 19,000 Kladovo – 21,000 Boljevac – 15,000 Majdanpek – 20,000 The largest city in the region is Zaječar, and therefore functions as its cultural, urban, and economic centre. It consists of four municipalities: Stari grad (old parts of the city: Vlačić, Kraljevica, Karađorđev venac, Šljivarsko brdo, Lubničko brdo, Oskoruša, Pazaršte, Zvezdan, Podliv, Veliki izvor), Kotlujevac (Ključ 1,2,3,4, Živinarnik, Selište, Vlaško brdo, Beli breg), Grljan (south suburban parts and Višnjar) and Salaš (north suburban parts). The largest municipality is Koltlujevac, with a population of over 25,000. Climate Zaječar, the biggest city in the region, has a humid continental climate (Köppen climate classification: Dfa), bordering on a humid subtropical climate (Köppen climate classification: Cfa). History Early Bronze Age pottery of the Kostolac-Kocofeni culture has been found throughout the region. During the Roman era, the area was administratively part of the Dacia Ripensis. During emperor Justinian's reign there were numerous fortifications in the area. Notable Roman sites include Timacum Minus, Trajan's Bridge, Diana Fortress, and others. The Bulgarian ruler Ivan Stratsimir (Vidin principate) and Wallachian Voivode Mircea the Elder controlled the territory of Podunavia until the Ottoman conquest in the 14th century. Several settlements in the region received Habsburg monarchy frontier status after the Treaty of Passarowitz (1718); the area became a frontier towards the Ottoman Empire. A peasant uprising took place in 1883 in the Timok Valley, in Eastern Serbia, known as the Timok Rebellion. The peasant movement