The most notable, żur (also called żurek, zalewajka, keselica or barszcz biały[1]), is considered a part of the national cuisine of Poland.

Sour cereal soup can be also found in Lithuanian, Ukrainian or Belarusian cuisine (as žur, kisjalica or kiselycia), a reminiscence of all these countries current territory being once in Commonwealth of Two Nations.

In Silesia, a type of sour rye soup known as żur śląski is served in a bowl, poured over mashed potatoes.

[5] Another similar soup, sometimes identified as identical with żur – but usually differentiated by its preparation with soured wheat flour rather than rye, is known as barszcz biały (lit.

Žur may also denote a thicker porridge, a type of kissel made of fermented oatmeal, which is known since the times of Kievan Rus'.

[13] It is a traditional Czech cuisine from poor folk food originating in the Northern Bohemia highland region of the Giant Mountains.

[11] Kyselo has been a traditional daily food of poor people in the Giant Mountain region for centuries, primarily in the winter.

[13][16] The Giant Mountain region is on the Czech–Polish border, and kyselo is a close relative of the Polish sour rye soup.

[13] The thickened broth is supplemented by onion sautéed in butter, boiled and then roasted potatoes and scrambled eggs and seasoned with salt and vinegar.

As a staple food, kyselo plays an important part in local legends and fairy tales, especially in connection to the mythical mountain lord Krakonoš (German: Rübezahl).

[25] In the Giant Mountains there is also a peak called the Kotel (Polish: Kocioł, German: Kesselkoppe) which means cauldron.