museum, director kenji shiga showed us everyday items that became artifacts. >> this is one of the things people want to come and see. a four-year-old boy was killed while riding this tricycle. it's grim evidence of the nuclear explosion.r temperatures reached 7,000 degrees. shiga told us these personal be belongings, including an incinerated school lunchbox burned by heat waves conveys how lethal and powerful the bomb was. "today there are 16,000 nuclear weapons on earth," he said, "so it's important to take another look at what happened here."it it's difficult to tell the's story, but you feel it's a story that must be told. >> reporter: this city straddles t a desire to move forward and to never forget. seth doane, cbs news, hiroshima, japan.