Originally, seven towers (from the south to the northwest: Katzenturm, Ochsenturm, Beckbomerturm, Koblenzer Torturm, Felsenturm, Niederburger Torturm, Mühlenturm) were erected for security. Today, only five of the original seven towers remain. The Beckbomerturm as well as the Niederburger Torturm were destroyed in the course of the centuries or have crumbled.