When the building of the former Minorite monastery in Celje was reshaped into a penitentiary in the 19th century, locals gave it the name Stari Pisker (English: "Old Pot"). Prior to 1941 it had been used as a prison for women; during the Second World War, German occupation forces used the site to commit many atrocities against civilians. In six out-of-court executions 374 hostages were shot in the yard, many others were tortured there. In December 1944 partisans attacked prison and freed 127 political prisoners. Today the site is administered as a dislocated permanent exhibition of the Celje Museum of Recent History, which holds a moving collection of farewell letters written by war prisoners held in the Old Pot who had learnt they would soon be executed.
In 1965 the prison was opened as a memorial site to victims of Nazi violence, with a memorial courtyard and a memorial room in the former torture-chamber. It was later renovated in 1995. Today, the building surrounding the memorial's inner yard is still used as a re-education establishment for juvenile offenders.
