If you liked the Barefoot Gen manga, the Anime-Planet community thinks you'd like:
Even those that survived the atomic bombing of Hiroshima couldn't escape its repercussions. Ten years after that fateful day, blast survivors still struggle with lingering radiation exposure and squalid living conditions. During this time, Minami Hirano ignores her worsening physical condition and tries to live her life as best she can, despite being haunted by what she saw and how she reacted during the event. Then, fifty years in the future, the city has been rebuilt and the radiation has subsided, but the ghost of the tragedy still looms in the minds of those that were left behind.
If you liked Barefoot Gen because of the heart wrenching story of surviving after an atomic bomb, not only physically but also mentally, then you'd probably like Yunagi no Machi, Sakura no Kuni. Although the latter is somewhat more serene and reminiscent in nature, they both show the aftermath of a weapon that killed hundreds of thousands of people, not only when it exploded but also many years after that. But most of all they're both a story about willing to live, about making the best of your life. The art styles are also somewhat similar; simple, but effective. So, if you've read this manga, please check Town of Evening Calm out. It's just one volume and incredibly touching.