This map approximately denotes the region of Germany, in which the "Schwenken" barbecue style is prevalent. The region encloses all of Saarland and parts of neighboring Rhineland-Palatinate (mainly the Hunsrück region).
See this Wikipedia article for more information on the style.

This work is based on commons file "Relief Map of Germany.svg" by TUBS.
Own work
Hierakares