Learn how scientists discovered a Holocaust escape tunnel at the Lithuanian site, Ponar using noninvasive techniques, in this NOVA Next article. Vilnius, Lithuania, was once home to over 100,000 Jews. However, during the Holocaust, 95 percent of Lithuanian Jews were killed. In 1944, 80 prisoners attempted to escape a mass burial pit through a hand-dug tunnel. Only 11 people survived; however, the story of their escape has been passed down through oral histories. The exact location of the tunnel remained a mystery until 2016. Advances in archaeological technology allowed researchers to search the area without disturbing the burial sites. This resource is part of the NOVA Next Collection.