The Alzette is a river with a length of 73 kilometres in France and Luxembourg. It is a right tributary of the Sauer, and ultimately to the Rhine. It rises in Thil near the town Villerupt in the Meurthe-et-Moselle département, France. It crosses the border with Luxembourg after 2.7 km. At Lameschmillen it is joined by the Mess. It flows through the Luxem…The Alzette is a river with a length of 73 kilometres in France and Luxembourg. It is a right tributary of the Sauer, and ultimately to the Rhine. It rises in Thil near the town Villerupt in the Meurthe-et-Moselle département, France. It crosses the border with Luxembourg after 2.7 km. At Lameschmillen it is joined by the Mess. It flows through the Luxembourgish towns Esch-sur-Alzette, Luxembourg City and Mersch, and empties into the Sauer near Ettelbruck.