Biała River (Vistula basin)

Biała
Biała River in Bielsko-Biała
Country	Poland
Basin features
Main source	Silesian Beskids about 1,020 m (3,346 ft)
River mouth	Vistula
Basin size	139 km2 (54 sq mi)
Physical characteristics
Length	28.875 km (17.942 mi)

Biała (German: Bialka) is a river in southern Poland, a right tributary of the Vistula, around 29 km (18 mi) long. It is the main river of the city of Bielsko-Biała and used to be historically important as a border river dividing not only Bielsko and Biała but for a few hundreds of years also the states of Bohemia (succeeded by the Habsburg Monarchy) and Poland.

Two sources of the river are located on the north-east slopes of the Klimczok mountain in the Silesian Beskids on the elevation of around 1020 and 900 m. The upper part the river, known as Białka (diminutive form of Biała), has characteristics of a mountain stream. The first settlement it runs through is the village of Bystra. Before Mikuszowice it joins with Biała stream beginning on eastern slopes of Magura mountain in Little Beskids, then the river veers north and on the length of 15.7 km (9.8 mi) it forms a pivotal line of the city of Bielsko-Biała, afterward it flows in between Czechowice-Dziedzice to the west and Gmina Bestwina to the east, and empties to Vistula River on the elevation of 240 m.

In the 13th century both banks of the river belonged to the Silesian Duchy of Opole and Racibórz but the valley of the river was yet sparsely populated defining a natural border between castellanies of Cieszyn and Oświęcim and ecclesiastical border between dioceses of Wrocław and Kraków. In 1290, in the process of feudal fragmentation of Poland the Duchy of Cieszyn, encompassing both Cieszyn and Oświęcim and so also both banks of the river, was split from it. Roughly at that time several new settlements were established alongside the river, including foundation of the town of Bielsko.