I meet historian Thomas Irmer in front of three tall pillars in Berlin, Rummelsburg. It's the entrance to a memorial site on the grounds of the former Rummelsburg workhouse.
The three pillars symbolize different time periods - from the late 19th century until the fall of the wall. Irmer says, "It used to be the biggest workhouse in Germany and nobody knows that it has been situated here in Rummelsburg. This history has been totally forgotten, really far, far away."
Today the blocks of red brick buildings are mostly condominiums. The former wash house is a day-care center. What used to be a hospital is now a hotel. Back in the 1870s the complex was set up for Berlin's poor.
"Most of the inmates were so called fringe groups like beggars, prostitutes, or homeless. They were sent here after they had already been to prison. They were sent here in order to change their habits by work," Irmer adds.
Thomas Irmer curated the open air exhibition at the historic grounds. It opened this year. He's selected 18 profiles of former inmates. They are displayed in front of the buildings that housed them. There's also an app that tells the story of this almost forgotten history. One of the inmates during the Nazi era was Auguste Löwenthal.
Here we hear some of her narrative from the app: "I was found guilty of committing Rassenschande (racial defilement), because I, as a Jewish woman, had also received 'Arian' clients."
Irmer continues, "The Nazis killed all Jewish inmates and they punished much more people and accused them of being a-social than in East Germany for example. The East Germans didn't kill any prisoners, so there are lot of differences."
During the time of the GDR the site functioned as the main male prison in East Berlin. Mostly political prisoners, many from non-communist countries ended up in Rummelsburg. It was secured like a fortress, an autonomous place, Irmer says.
"The main connection to the outside were rats, which were coming through pipes and underneath the earth to this complex. The prisoners who we talked to they always remember the rats," he continues.
The Rummelsburg prison closed in 1990 shortly after Germany's reunification. In January of 1990 ousted East German leader Erich Honecker himself spent a night in the prison hospital. In the last month of its existence, the inmates began to protest a system that had run its course.
Today the historic location attracts young families, because it's close to the water and not far from Berlin's center. Irmer's permanent exhibition reminds us of Rummelsburgs more complicated past and the people who were forced to live there.
He he says he hopes "to create some sensibility for dealing with the poor, even today."