Junko Istibashi was born in the year 1939 in a tiny agricultural town in Fukushima. Her love of mountain climbing started at the meer age of ten after she was taken by a teacher to hike Mount Nasu in Nikko National Park. Junko was always aware of her duties of being a women in the future. She must pursue a higher education and find a proper job in the “conservative Japan”. ​​​​​​​

She later went to study English and American literature at Showa’s Woman University, and still climbed regularly. Junko graduated in 1962, and ended up joining several mountain climbing groups. While doing this, she was looking for climbing partners to go on expeditions with. “... groups were largely male-dominated, and Junko’s enthusiasm was often met with judgement by the groups’ younger men, who believed her to be in fact looking for a husband, rather than teammates”. She later met her husband, Masanobu Tabei in 1965, during an expedition and had two children with him (daughter Nariko, son Shinya). Her mother did not approve of her marriage to Masanobu because he had not gone to university. However, Junko did not care because she finally found a partner who shared her love climbing and supported her expeditions. 

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