Wikipedia
Weißwurstäquator
The Weißwurstäquator (, white sausage equator) is a humorous term describing the supposed cultural boundary separating Southern Germany, especially Bavaria, from Central Germany.
It is named for the Weißwurst sausage of Bavaria. There is no precise definition of the Weißwurstäquator; it is sometimes taken to correspond with the linguistic boundary known as the Speyer line separating Upper German from Central German dialects, roughly following the Main River. It is sometimes taken to run further south, more or less along the Danube, or between the Main and the Danube, roughly along the 49th parallel north circle of latitude.