An extension is being built on Rathausplatz for Cologne's oldest museum. The clearly defined structure with its elaborate brick façade ingeniously reflects its immediate surroundings: the main museum building designed by O. M. Ungers, the town hall and the Gürzenich concert hall. 1000 m2 of additional art exhibition space is being created on three levels. The extension is the finishing piece of the impressive architectural ensemble on Rathausplatz.