The river Bille is a small, slow-flowing river in Stormarn, Schleswig-Holstein and Hamburg, a right tributary of the Elbe. Its source is near Linau, north of the Hahnheide forest. It then flows south of Trittau, representing the border between Stormarn and Lauenburg, continues south of Reinbek and reaches the river Elbe near Billwerder. A lot of old estates and tasteful parks are laid out along its riverbank.