The river Bille is a small, slow-flowing river in Stormarn, Schleswig-Holstein and Hamburg, a right offshoot of the Elbe. Its wellspring is near Linau, north of the Hahnheide woodland. It then flows south of Trittau, landmarking the border between Stormarn and Lauenburg, runs on south of Reinbek and reaches the river Elbe near Billwerder. A lot of old landed seats and winsome parks are laid out along its riverbank. Its overall length is 65 km.
The Bille is one of three rivers which flow through the city of Hamburg, the other two being the Elbe and the Alster.
Wikipedia https://en.wikipedia.org/wiki/Bille_(Elbe)
Coordinates 53°31'10.884" N 10°7'19.942" E