Palais du Rhin

The curved, river-facing façade of Savonnières limestone is divided into nine window bays, with the central three projecting as a semicircular bay crowned by balconies. A colossal order of engaged columns with corner pilasters frames the front, and an outdoor staircase opens the view toward the river. This nine-bay front with its semicircular central projection and staircase was considered unique in Cologne. The building also features a tall raised basement with barred windows and a mansard floor. Alongside the Boisserée Villa, the palace is regarded as one of the few surviving examples of grand bourgeois riverside architecture in this stretch of the Rhine.

An investor acquired the property in December 2008 to convert it into luxury apartments following extensive renovation, with construction beginning in September 2012. The building spans 15,800 m² (19,300 m² gross floor area), and the piano nobile forms its own residential floor of about 600 m². The two-story mansard roof was rebuilt to match the original massing, while sandstone cornices and balustrades were restored in keeping with heritage requirements. Completed in March 2014 and renamed "Palais du Rhin," the building now holds eleven apartments, with its 12,300 m² park reserved for residents. In June 2021 Sotheby's chose the Bel Etage as its sixth European location alongside London, Paris, Geneva, Zurich, and Milan, holding its opening auction there in September 2021.