The Kiel- or Zimmergraben (Keel Ditch or Timber Ditch), situated between the Lower Town (Niederstadt) and the Bleihof Island (Lead Yard Island), takes its name from the Zimmerhof (timber yard) and the Kielbank (keel bench) that already existed on the Bleihof Island during the time of the Teutonic Order. The Zimmerhof was a yard where shipbuilding timber was stored and worked; the Kielbank was the apparatus on which ship keels were constructed.

The present-day street Am Kielgraben is still unnamed on 18th-century maps. In 1796, it was called "Beim Zimmerhof" (At the Timber Yard), and from about 1817 it received its final name "Am Kielgraben" (At the Keel Ditch).

History