This pedestrian tunnel in the city of Zagreb runs underneath the historic neighborhood of Grič. Built during World War II, the tunnel was originally intended to serve as a bomb shelter and transport link through the hill of Gornji Grad. It measures 350 meters long and up to 5.5 meters wide, connecting Mesnička and Stjepan Radić Streets. Construction began in 1943 and finished 1944. The tunnel was harshly criticized for its expense, and many argued that it was not necessary. Work continued nevertheless, though changes were made to the project….