Excavations
Since August 2007 excavations have been under way in the Town Hall Square. This is where, in the Middle Ages, one of the largest and even then, oldest urban Jewish Quarters was located. The excavations have proved: the oldest synagogue north of the Alps known hitherto was situated in Cologne. It can be dated back to at least 800 AD, the Carolingian epoch. The Carolingian Synagogue is built on a classical structure of the fourth century. An integral part of the monument is a basin that was used in a uniform manner in all subsequent phases of the building. Its 1000-year long utilisation was detected in thermoluminescence investigations. The finding could be an indicator for a synagogue that is even older.
In spring 2009 the excavations at the southern side of the Town Hall Square began. The new excavation area exposed the foundations and cellar walls of large Romanesque and Gothic houses.
In 2010 the excavations are continuing at the northern side of the Town Hall Square. This is where the southern part of the Praetorium is expected to be found.