Ūla
The Ūla () is a river which starts in northern Belarus and flows into the Merkys river, southern Lithuania. It flows in a general north-western direction. It starts as a confluence of two channeled rivers, Provozha (Провожа) and Luchka (Лучка) by the  village. From Luchka to Dubičiai it is known as Pelesa (Padzeyka in Belarus). Its total length is 84 km, of which 13,5 km are in Voranava District, Grodno Region, Belarus, 3 km are along the Belarus-Lithuania border, the rest is in Varėna District, Lithuania, of which part flows through the  and then in the Dzūkija National Park. It flows into Merkys near Paūliai. See also
Kotra (river), the case of Pelyasa/Pelesa river bifurcation. References 

Rivers of Grodno Region
Rivers of Lithuania
International rivers of Europe
Rivers of Belarus
Belarus–Lithuania border