Sauer

The Sauer or Sûre is a river that flows through Belgium, Luxembourg, and Germany. It is a left tributary of the Moselle with a total length of 173 kilometers (107 mi).

The Sauer River rises near Vaux-sur-Sûre in the Ardennes region of southeastern Belgium, flows eastward, and forms the border with Luxembourg near Martelange. It runs for 13 kilometers (8 miles) north of Martelange, forming the border between Belgium and Luxembourg. It flows west of Esch-sur-Sûre into the Upper Sûre Lake, which was created by the Esch-sur-Sûre Dam and gives its (French) name to the Luxembourgian commune of Lac de la Haute-Sûre. Following Ettelbruck and Diekirch, the Sauer forms the border between Luxembourg and Germany for the final 50 kilometers (31 miles), passing Echternach before emptying into the Moselle in Wasserbillig. Tributaries include the rivers Wiltz, Alzette, White Ernz, Black Ernz, Our, and Prüm.

Length: 173 km (107 mi- shared with Germany and Luxembourg)