Usora (Serbian Cyrillic: Усора) is a river in central-northern Bosnia and Herzegovina. It bigins at the confluence of two smaller Usora rivers, Mala Usora and Velika Usora, at the town of Teslić. Usora runs for some 20 km northeast of Teslić, and becomes a left tributary of the Bosna River, south of Doboj. Serbian Cyrillic is the Serbian variant of the Cyrillic alphabet. ... Confluence of Rhine and Mosel at Koblenz In geography, a confluence describes the point where two rivers meet and become one, usually when a tributary joins a more major river. ... Teslić (Теслић) is a town and a municipality in northern Bosnia and Herzegovina, located southwest of Doboj, west of TeÅ¡anj and southeast of Banja Luka. ... Look up tributary in Wiktionary, the free dictionary. ... The Bosna is the third longest river in Bosnia and Herzegovina, and is considered one of the countrys three major internal rivers, along with the Neretva and Vrbas. ... Doboj (Cyrillic: Добој) is a city and a municipality in the Republika Srpska entity, Bosnia and Herzegovina, situated on the river Bosna. ...