Yoshiko Kajimoto was aged 14 and working in a Hiroshima munitions factory when the atomic bomb was dropped on the morning of August 6, 1945.
While all her family survived that day, radiation would kill her father a year later and radiation illness would confine her mother to hospital for 20 years.
Yoshiko gave up her dream to train as a teacher and had to work instead to earn money to raise her three brothers.
She’s now 85 and a mother, a grandmother and a great-grandmother.
Here is her account of the day the bomb fell on her city:
Commenting on today’s visit by Mr Obama, she said: