The river, which is about 65 kilometers long, can be roughly divided into three sections: The Upper Bille designates the small river from its source near Linau east of Hamburg in the Duchy of Lauenburg to Bergedorf. The middle Bille meanders from Bergedorf to Billstedt. There begins the last, heavily canalized section of the Lower Bille, which finally flows into the North Elbe at the Brandshofer Lock between Hammerbrook and Rothenburgsort near the Elbe bridges.