Western Bug in the context of "List of longest rivers of Ukraine"

The Belarusian-Ukrainian border (Belarusian: Беларуска-ўкраінская граніца, romanized: Bielaruska-ŭkrainskaja hranica, Ukrainian: Білорусько-український кордон, romanized: Bilorus'ko-ukrajin'skyj kordon) is the state border between Belarus and Ukraine with a length of about 1,084 km (674 mi). It starts from the triple junction with Poland to the west and stretches to the triple junction with Russia to the east. The tripoint border at the triple border junction of Belarus, Russia and Ukraine is marked in the form of a monument, while at the other border junction there is a river, the Western Bug that coincides with the border of Poland.

The Southern Bug, also called Southern Buh (Ukrainian: Південний Буг, romanized: Pivdennyi Buh; Russian: Южный Буг, romanized: Yuzhny Bug; Crimean Tatar: Aq Suv; Romanian: Bugul de Sud or just Bug), and sometimes Boh River (Ukrainian: Бог; Polish: Boh), is a navigable river located in Ukraine. It is the second-longest river flowing exclusively in Ukraine.

While located in relatively close proximity, the river should not be confused with Western Bug or Bug which flows in opposite direction towards Baltics. The source of the Southern Bug is in the west of Ukraine, in the Volhynian-Podolian Upland, about 145 kilometres (90 miles) from the Polish border, from where it flows southeasterly into the Bug Estuary (Black Sea basin) through the southern steppes (see Granite-steppe lands of Buh park). It is 806 kilometres (501 miles) long and drains 63,700 square kilometres (24,600 sq mi).

The Buzhans were a tribal union of Early Slavs, which supposedly formed the East Slavs in southern Russia and the Volga region. They are mentioned as Buzhane in the Primary Chronicle. Several localities in Russia are claimed to be connected to the Buzhans, such as Sredniy Buzhan in Orenburg Oblast, and Buzhan and the Buzan River in Astrakhan Oblast.

Some theories say that the name of the tribes could be connected to Western Bug, in Ukraine, where they chose to settle down. According to the Bavarian Geographer, the Buzhans had 230 "cities" (fortresses). Some historians believe that the Buzhans and the Volhynians used to be called the Dulebes.

Ukraine has around 23,000 rivers, with most of the rivers draining into the Black Sea and Azov Sea and belonging to the larger Mediterranean basin. Those rivers mostly flow in a southerly direction, except for the Pripyat tributaries in Volhynia and Dniester tributaries in Prykarpattia. A few western Ukraine rivers drain to the north west through Poland to the Baltic Sea, as part of the Western Bug drainage basin. The most notable rivers of Ukraine include the Dnieper, Dniester, Southern Bug, and Siverskyi Donets. The longest river is the Dnieper, the longest tributary is the Dnieper's tributary Desna. Two of the Danube's tributaries in Ukraine, the Prut and the Tysa, are longer than the main river within Ukraine.

In 2013, in accordance with the Water Framework Directive, the territory of Ukraine has been divided into nine hydrographic zones [uk] according to major river basins, including the basins of the Vistula (Western Bug and San), Danube, Dniester, Southern Bug, Dnieper, Don, the rivers of the Black Sea littoral, the Sea of Azov littoral, and separately the rivers of Crimea. The biggest river basin by area is the Dnieper which is subdivided into the Pripyat basin, Desna basin, basin of Middle Dnieper, basin of Lower Dnieper. Beside Dnieper, basin of the Danube zoning is also subdivided into basin of Tysa, basin of Prut and Siret, and basin of the Lower Danube.