Template:Redirect Template:Infobox river The Olza (Template:Langx, Template:Langx) is a river in the Czech Republic and Poland, a right tributary of the Oder River. It flows through the Silesian Voivodeship in Poland and through the Moravian-Silesian Region in the Czech Republic. It is Template:Convert long. The river forms a significant part of the Czech-Polish state border.

EtymologyEdit

The name is derived from the Proto-Slavic word oliga, meaning "a river rich in water".<ref name=ct>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The origin of the name was demonstrated in 1900 by Czech linguist and writer Vincenc Prasek and the revelation was confirmed by various etymological studies in the 20th century.<ref name=Gaw>Template:Cite journal</ref> There was also a theory that the name is a derivative of the Germanic Aliza, meaning 'flow'.<ref name=ct/>

The oldest written mention of the Olza is in a letter written by Duke Mieszko in 1290.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The river was then mentioned in a written document in 1611 as the Oldza.<ref name=Cicha>Template:Cite book</ref> At the end of the 19th century, with the rise of mass nationalism, both Polish and Czech activists claimed the name Olza to be not Polish enough, on the one hand, and insufficiently Czech, on the other.<ref name=Gaw/>

Local people always used the Olza name, regardless of their national or ethnic origin. However, the central administration in Prague saw Olza as a Polish name and when most of the river became a part of Czechoslovakia in 1920, it tried to change its name to the Czech form, Olše. However, a degree of dualism in the naming persisted until the 1960s, when the Central State Administration of Geodesy and Cartography ruled that the only official form in the Czech Republic was Olše. This modern Czech name literally means 'alder' in Czech.<ref name=Cicha/><ref name=Gaw/>

CharacteristicEdit

File:The source of Olza.JPG
Spring of the Olza

The Olza originates in the territory of Gmina Istebna in the Silesian Beskids at an elevation of Template:Cvt and flows to the Czech-Polish border in Bohumín/Gorzyce, where it merges with the Oder River at an elevation of Template:Cvt. Its drainage basin has an area of Template:Convert,<ref name=mze>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> of which Template:Convert is in the Czech Republic.<ref name=dibavod>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The average discharge at its mouth is Template:Convert.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The Olza forms two sections of the Czech-Polish state border with a total length of Template:Convert.<ref name=pod>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Length figures vary by source. According to the newest official measurements, the Czech part of the river (including the Czech-Polish state border) is Template:Convert long.<ref name=dibavod/><ref name=chmi>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The length of the Polish section of the river to the first crossing of the state border is usually stated as Template:Convert,<ref name=pod/><ref name=universum>Template:Cite book</ref><ref name=pwn>Template:Cite book</ref> which means that according to the latest measurements, the river has a total length of Template:Convert. However, based on older measurements, the total length of the river is stated as Template:Convert,<ref name=universum/><ref name=pwn/> Template:Convert<ref name=mze/> or even Template:Convert.<ref name=Cicha/>

The longest tributaries of the Olza are:<ref name=chmi/>

Tributary Length (km) River km Side
Stonávka 33.7 19.7 left
Petrůvka / Pietrówka 31.4 12.8 right
Szotkówka 21.3 10.2 right
Lomná 17.6 64.2 left
Ropičanka 16.5 38.7 left
Tyra 13.0 45.9 left
Bobrówka 12.7 35.1 right
Hluchová 12.6 55.3 right
Kopytná 11.7 55.2 left
Lutyňka 10.7 3.3 left

CourseEdit

File:Olše v Bukovci.jpg
Upper course of the Olza in Bukovec
File:Řeka Olše (červenec 2022).jpg
The Olza forming the border between Cieszyn and Český Těšín

The river flows through the territory of Istebna in Poland, then crosses the Czech- Polish border and flows through territories of Bukovec, Písek, Jablunkov, Návsí, Hrádek, Bystřice, Vendryně, Třinec and Český Těšín. Here it begins to form the state border with Cieszyn, Pogwizdów and Kaczyce on the Polish side and Chotěbuz on the Czech side. The river then continues through the territories of Karviná, Dětmarovice and Petrovice u Karviné before it begins to form the state border again, which lasts until its mouth. In this section, it flows along the territories of Godów and Gorzyce in Poland and Dolní Lutyně and Bohumín in the Czech Republic.

Bodies of waterEdit

There are 690 bodies of water in the Czech part of the basin area. The largest of them is the Těrlicko Reservoir with an area of Template:Cvt, built on the Stonávka.<ref name=dibavod/>

CultureEdit

The river is a symbol of the Trans-Olza region, which lies on its west bank, constituting a part of the western half of the historical region of Cieszyn Silesia. The river is depicted in the words of the unofficial anthem of this region and of local Poles, Płyniesz Olzo po dolinie ("Thou flowest, Olza, down the valley"), written by Jan Kubisz.

FaunaEdit

Protected animals that live in the river include the brook lamprey, schneider, European bullhead and alpine bullhead. River trout and grayling are commonly found in the river. Protected animals that live on the river banks include the Eurasian otter and common kingfisher.<ref name=pod/>

TourismEdit

The Olza is suitable for river tourism. The river is navigable for most of the year. Most of the river is suitable even for less experienced paddlers.<ref name=ct/>

See alsoEdit

ReferencesEdit

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External linksEdit

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