Former librarian Gen Yamazaki fixes his eyes on a map he found in the stack room at the National Diet Library in Tokyo in 1981.

It shows Hachioji, a city on the outskirts of Tokyo, outlined in red.

The 86-year-old Yamazaki knows the red markings indicate areas burned down in U.S. air raids in the final days of World War II, and his mind is cast back to the hardships he and others suffered at that time.