The Römerturm (“Roman Tower”) in Cologne was once the North-western tower of the surrounding wall of the Roman colony Colonia Claudia Ara Agrippinensium and dates back to the second and third century. The entire facade of the tower was ornamentally designed with stones of various colours. The crown of merlons on top of the building was added at end of the twentieth century. Over the course of past centuries, the tower was part of a monastery (Poor Sisters of St. Clare) and at a later date, part of an apartment building. It was temporarily owned by the City of Cologne and has been listed for preservation since 1980. Today, the Römerturm is privately owned.