The occasion is being commemorated in Japan, where the average age of survivors is over 80 years - making the preservation of their memories an important task.
Among the tributes, historical timelines, and eyewitness account published this week is a short animation from the BBC, in which an elderly Japanese poet recounts seeing the bomb explode over the city when she was just 14 years old.
84-year-old Bun Hashizume was only a young girl on August 6, 1945. Despite her young age, she was working in the Ministry of Communications in Hiroshima - filling in for the men at war.
"I was standing by a window on the third floor, when I saw a powerful flash. I thought the sun had fallen down in front of my eyes. In a split second, I saw rainbow coloured rays everywhere.
"That was the moment the bomb exploded."
Hashizume lost her brother in the blast, and her family only discovered she survived the next day, after she left hospital. She has been plagued by health issues from the fallout ever since.
Created by CBBC, the children’s wing, the animation is designed to teach young children about the suffering from the perspective of a child, and is airing tonight as part of Newsround’s special on the anniversary of the bombings.
In a blog post about this video, editor of Newsround, Lewis James, wrote about the difficulty in explaining traumatic events to children - something applicable to news coverage for many adults, too.
"We look at how we might be able to tell it in a way which minimises any distress," he wrote.
"We are particularly careful about distressing footage, as it is the thing most likely to upset children but for some stories the only available footage can be upsetting ... one way of dealing with this is by using animation."
The survivors of Hiroshima and Nagasaki today are all 70 years old at the very least. Their stories come from being children during the world-changing event, and their stories are important to preserve.
5,359 "hibakusha" - those affected by the bombings - died in the last year, bringing the total death toll from the Hiroshima bombing to 297,684.