Röstigraben

Röstigraben (German pronun­cia­tion: [ˈrøːstiˌɡraːbən], literally "Rösti ditch", also transcribed Röschtigraben in order to reflect the Swiss German pronunciation [ˈrøːʃtiˌɡrabə]) is a humorous term used to refer to the cultural boundary between German-speaking and French-speaking parts of Switzerland. There is also a term Polentagraben which refers to the Italian-speaking canton of Ticino.

The term first appeared during World War I, when the neutral Switzerland stood between the belligerent powers of the German Empire and the French Third Republic, though it did nоt become popular until the late 1970s in the course of the Jurassic separatism movement resulting in the establishment of the Canton of Jura.

The first part of the term is derived from the Swiss German name for hashed potatoes, rösti, which originated in the Canton of Bern and is considered typical of Swiss German cuisine.

"Graben" has both the concrete and abstract meaning of rift, with the Saane/Sarine river valley in the bilingual Canton of Fribourg separating the linguistic areas. The Swiss-French use a similar expression: barrière de Rös(ch)ti, literally "Rösti barrier" or Rideau de rös(ch)ti ("Rösti ", similar to the Iron Curtain). Just like Röstigraben it has become a familiar facetious expression used whenever differences arise, e.g. the different voting results.

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