The Rhein-Neckar-Kreis is a district in the northwest of Baden-Württemberg, Germany. The administrative headquarters are based in the city Heidelberg, which is a district-free city.
As of 2019, the district is the most populous in Baden-Württemberg.
Wikipedia https://en.wikipedia.org/wiki/Rhein-Neckar-Kreis
Coordinates 49°24'33.689" N 8°41'41.006" E