The Mausoleum of battle and Martyrdom is located in the left wing of the Ministry of Education, which housed the headquarters of the Security Police and Security Service during the occupation. The basement was used as an investigative prison

Visitors can access and see collective cells, known as the "trams", hallways, isolation chambers and the office of the Gestapo guard, in which hearings were held. Walls, window frames and floors are covered with thousands of inscriptions and texts of prayers, reflections about death, initials, names, nicknames, prison calendars, clocks, crosses and numerous carvings and drawings – a legacy of the people who suffered so brutally in this place.