Its task was to protect the expanded Rhine harbour and the Rhine crane, which still exists today as a gauge house. Furthermore, the structure was equipped with an icebreaker with humped ashlars, which protected ships and the harbour. When the Prussian city wall was demolished at the end of the 19th century and the Rhine facilities were extended, the Kavalier was partially demolished. After the harbour was moved to the Moselle, it was converted into a viewing platform. After the Second World War, the Kavalier was rebuilt.