Wikipedia
Gropenborn
The Gropenborn is a tributary of the Sieber, northeast of Sieber in the district of Osterode am Harz in Lower Saxony. It rises to over 560 meters above sea level and flows mostly to the northwest, where it is separated from the Gropenbornskopf by the Sieber. After about 2 km river he finally ends at an altitude of less than 340 m in Sieber in the Sieber. The natural Gropenborn is a river of Class I-II. Dominant organism group are caddisflies with 12 species.