The Hiroshima Peace Memorial is located downtown and houses several memorials to the atomic bomb. One one side, there's the museum, and on the other the dome where people can see the results of that harrowing day on August 6, 1945. Each year, a tribute to the victims is performed and anti-nuclear and pro-peace messages are released in in the park. There are many school children around, and it's a pleasant place despite what happened there. If you come to Japan, I recommend visiting.