The bastion Martin was already built in the first years of the fortress construction until 1673. During the 1920s, it was breached for the construction of the Lauentorstraße. Since that time the top of the bastion has been separated from the core of the fortress. A viewing platform was built on the bastion remnant until 1928. In the course of the breakthrough work, a former city wall tower from 1423 was uncovered at this location. Its interior was incorporated into the new wall facing Lauentorstrasse as a gate motif.