From May through September, The Estonian Institute of Historical Memory has opened an exhibition area 'Communism is Prison' which introduces the nature of communist ideology, its international crimes, stories of its victims, and the history of the complex. The communist regime in Estonia, on periods of 1940-1941 and 1944-1991, imprisoned innocent people in the historical Patarei fortress on ideological pretext. The exhibition area is the first stage of establishing the International Museum for the Victims of Communism and research centre that will be built in the Patarei complex in the coming years. Entrance to the area is from the side facing the Port of Tallinn from Suur-Patarei street through the gate, or from the seaside promenade through the small gate.