Granusturm

The more than 20-metre-high Granus Tower towers almost fearsomely over today's ensemble of buildings around Aachen Town Hall. Together with Charlemagne's Royal Hall, it was built at the end of the 8th and beginning of the 9th century. Additions followed in the 14th and 20th centuries. What function did the building, which is no longer open to the public, once have? Opinions are divided on this. Originally, it was probably an elaborate staircase, but was also used as the tower guard's apartment and later even as an archive and prison.