Based on events of the first successful expedition to climb the summit of Mt Qomolangma (Mt Everest) using the treacherous north route (from Tibet in China) in 1960. The trio who reached the summit on 25th May 1960 were the first climbers who do so without supplement oxygen when it ran out and they became the 7th, 8th and 9th summiteers of Everest.Edit Translation