Luxembourg and Germany share a unique border arrangement over the Moselle, Sauer, and Our rivers, where the waterways are governed jointly by both nations rather than divided by a straight boundary line. This setup, known as the German-Luxembourgish condominium, places the rivers, their islands, and several bridges under shared sovereignty. This unusual system traces its roots back to the Congress of Vienna in 1815, when borders were redrawn across Europe following the Napoleonic Wars.
According to Article 25 of the Final Act of the Congress of Vienna, the rivers were established as jointly owned territories, bypassing the traditional method of dividing them along a median line. The arrangement was later solidified by treaties in Aachen in 1816 between the Netherlands, which governed Luxembourg at the time, and Prussia. As Luxembourg eventually gained independence and Prussia became part of the German Empire, the original agreements from the 19th century remained in effect, shaping the modern border between Germany and Luxembourg.
The issue of bridges spanning these shared rivers was unresolved for many years. It wasn’t until the Moselle was canalised that discussions commenced in 1979 to address this ambiguity. A pivotal border treaty signed in 1984 included these bridges and footbridges within the shared territory, providing clarity.
Today, both German and Luxembourgish laws apply to this shared region, managed through a system of concurrent jurisdiction. Bilateral agreements assist in resolving conflicts that arise. Police forces from both countries are authorized to operate within this territory, with joint patrols being a common practice. Officers from either country can take action when offenses occur on these shared rivers or bridges, with jurisdiction over subsequent legal proceedings determined by factors such as the individuals involved and the specifics of the incident.
This arrangement remains a rare example of shared sovereignty in Europe, creating a border that functions differently from the conventional boundaries typically seen between nations. It reflects a collaborative approach to governance and law enforcement, maintaining a peaceful coexistence along these historically significant waterways.