Hiroshima and Nagasaki were the only two cities in Japan during 1945 that held Catholic diocese.

The atomic bomb that detonated in Hiroshima only had 1.7 percent of it's material fission and was considered very inefficient.

Twenty or more US Airmen were in Hiroshima as POWs when the Atom Bomb fell. SSG Ralph J. Neal and another Airman, Norman Brissette, survived the initial blast by jumping into a cesspool, only to die thirteen days later from radiation poisoning.

The destruction of Hiroshima was caused by only half a gram of matter being converted to energy: the weight of a butterfly.

The city of Hiroshima, Japan distributes seeds and saplings of trees which survived the atomic bomb as a symbol of peace and resilience.

The American public found out about the existence of the atomic bomb only sixteen hours after the bombing of Hiroshima.

Honolulu, Hawaii is sister cities with Hiroshima, Japan. This is because the first wave of Japanese immigrants to Hawaii arrived from Hiroshima in the late 19th century to work in the sugar industry.

The United States bombing of Hiroshima and Nagasaki needed approval of the United Kingdom as stipulated in the 1943 Quebec Agreement.

In September 1945, Australian journalist Wilfred Burchett defied US restrictions and snuck into Hiroshima by train. Burchett was the first to tell the world about the effects of radiation on the victims of the bombing, which the US denied both before and after his story was published.

Kyoto was actually at the top of the list of targets for the atomic bomb, not Nagasaki nor Hiroshima. Secretary of War Henry Stimson ordered for the ancient city with its thousands of palaces, temples, and shrines to be removed from the list, but the military kept on putting it back.

The Japanese command didn't realize Hiroshima had been totally destroyed until almost a whole day after it happened. Vague reports of some sort of large explosion had begun to filter in, but the Japanese high command knew that no large-scale air raid had taken place over the city.

Dr. Seuss drew anti-Japanese cartoons during WWII. When he met the survivors of Hiroshima, he realized "A person is a person no matter how small". He later created Horton Hears a Who! as an apology, dedicating it to a Japanese friend.

In World War 2, Allied bombers frequently dropped leaflets warning Japanese citizens to evacuate when they were about to bomb a city, including Hiroshima.

After Japan's surrender in WWII, Americans sent many Japanese soldiers returning to their homeland through Hiroshima to impress upon them how defeated Japan was.

In Japan, Hiroshima Peace Flame has been burned continuously since it was lit in 1964, and will remain lit until all nuclear bombs on the planet are destroyed and the planet is free from the threat of nuclear annihilation.

Godzilla was originally created as a metaphor for the the relationship between humans and nuclear weapons. Its skin is not based on reptile scales but the burn wounds found on the survivors of the Hiroshima bombing.

The same bomber group that nuked Hiroshima and Nagasaki, the 509th Composite Group, was also the first U.S. Military group to respond to the 9/11 attacks. The group was at the time (2001) and still is known as the 509th Bomb Wing, stationed in Whiteman AFB, Missouri.

In 1927, a 12-year-old boy rode along with stunt pilot Doug Davis, throwing Baby Ruth candy bars down over a racetrack as part of a promotion. The boy loved the experience, and would grow up to be a pilot… of the Enola Gay, the plane that dropped the atomic bomb on Hiroshima.

The parts of Hiroshima and Nagasaki that were destroyed by the atomic bombs have been rebuilt and are safe to visit.

Many US military officials, even war hawks such as Douglas MacArthur and several fleet admirals, opposed the usage of atomic bombs in Hiroshima and Nagasaki as unnecessary and cruel. Curtis LeMay even went as far as to say "The atomic bomb had nothing to do with the end of the war at all."

Paul Tibbets -the pilot who dropped the Hiroshima bomb- requested not to have a grave, so anti-nuclear activists wouldn't protest on it.

On the day of bombing of Hiroshima, within the first three seconds, thousands of people were incinerated as the temperature at the burst-point reached 60 million degrees centigrade- 10000 times hotter than the Sun's surface.

The U.S banned books and films about the Hiroshima and Nagasaki bombings in Japan as well as all satirical cartoons of General MacArthur.

Hiroshima is one of the only places outside of the United States to observe Martin Luther King Day because he wrote a letter to Japan weeks before his death, requesting to visit the county and spread his message of peace.

Eizō Nomura is a Japanese man who survived the Hiroshima explosion in a basement only 170 meters from ground zero. He lived for another 37 years.