Buchenwald concentration camp
A photo provided by the U.S. Army, taken April 16, 1945, of people in the Buchenwald concentration camp, including Elie Wiesel, seventh from left in the middle bunk, who went on to win the Nobel Peace Prize. A new survey found that many Americans lack basic knowledge of the Holocaust -- especially 18 to 34-year-olds, or so-called millenials. (United States Army via The New York Times)