Geisa

Geisa is a town in the Wartburgkreis district, in Thuringia, Germany. It is situated in the Rhön Mountains, 26 km northeast of Fulda. The near border with Hesse was the border between West Germany and the GDR during the Cold War. Thus, Geisa was in the East German border restriction area of the former inner German border, which meant that until reunification access to the town was limited. The town is the westernmost municipality in what was formerly East Germany.
Geisa is a town in the north of the Rhön Mountains in Thuringia. It is located on the Ulster River. The region is also referred to by the old name of Buchonia. The closest city is Fulda.

Wikipedia