Gdanisko - this tower extends beyond the walls of the castle in Malbork (Marienburg), performing an observation and defensive function but above all a sanitary facility. The waste immediately fell to the fosse, from where it flowed to the Nogat River. It was a very neat and sophisticated solution to the hygiene issue. However, it was not easy task to get to that tower, because in order to achieve the destination, you had to walk about a 60-meter corridor. What might happen in case, if someone had a really argent need?