The white sausage equator (Weißwurstäquator) divides northern and southern Germany. The rösti curtain (Röstigraben) divides German-speaking and French-speaking Switzerland.
Europe is full of borders and boundaries, some political, some linguistic, and some just plain funny. The Weißwurstäquator and the Röstigraben are tongue-in-cheek demarcations between different parts of Germany and Switzerland respectively. Both are defined by cuisine.
White sausage (Weißwurst ) is a common breakfast food in Bavaria. It’s a spiced veal and pork sausage cooked in water and served with mustard and pretzels. You don’t eat the skin of the sausage. Instead, you peel the skin off either side and suck the sausage out from within. More genteel diners might slice it in half instead.
Bavarians consume this white sausage but Germans to the north… not so much. This boundary between the two parts of the country, cultural and culinary, is known as the white sausage equator. The precise location of the line is ambiguous, but the 49th parallel is a common border. The town of Zwiesel even set up a Weißwurstäquator monument in 2013 (see the third link below).
A similar food border exists in Switzerland. Rösti is a kind of delicious potato fritter common in German-speaking parts of the country. But, like the white sausage, it is less popular and less tied to cultural identity in French-speaking Switzerland. This is the Iron Curtain of rösti, the Röstigraben.
In Switzerland the rösti curtain has become a kind of metaphor for the cultural divisions between the two regions. On the German side, stereotypically conservative and fiercely neutral. On the French side, less traditional, less strict, and more tolerant of connections with the European Union. And the humble rösti serving as a point of division between the two.
The reality on the ground rarely matches these stereotypes, of course. But in the last year one significant split along the Röstigraben bubbled to the surface. Covid-19 infection and mortality rates were much higher on the French side. The Röstigraben has become the Coronagraben.