It is a pedestrian tunnel located in the center of Zagreb, under the historical district of Grec, hence its name. The suff of its construction in World War II was to protect people from air raids. The tunnel consists of a central hall connected by two lanes to Mesnica Street in the west and Stjepan Radek in the east, as well as four lanes extending to the south. The tunnel is 350 meters long and 3.2 meters wide. It has many distinctive artworks and some sculptures, and the staff advises visitors to seek refuge in shelters in case of war.