Mount Everest has revealed many secrets down the years.
But among the annals of celebrated triumphs and glorious failures, one of the great Everest achievements has remained a mystery - until now.
Lhakpa Sherpa, a 42-year-old mother-of-three who lives in suburban Connecticut and works at a 7-Eleven shop, has been revealed as the greatest female Everest climber of all time, having reached the summit on six occasions.
She is currently at Advanced Base Camp in Tibet and due to make her seventh ascent later this week.
For years there have been whisperings about an almost-mythical Nepali woman who had conquered Everest half a dozen times.
But virtually nothing was known about Lhakpa and her remarkable story, partly because Sherpas and their mountaineering achievements do not receive the credit they deserve, but also because she shunned the limelight.
Lhakpa, whose name in Nepali means Wednesday - the day she was born - grew up with 11 brothers and sisters high in the Himalayas. By the age of 15 she was working as a "kitchen boy" for a mountaineering company.
"I have seven sisters, but my mama say I mostly look like a boy. 'Whatever boy doing, you doing. You never doing girl things. Mostly you're doing boy things'," Lhakpa told Outside magazine.
She wanted to follow in the footsteps of Pasang Lhamu, the first Nepali woman to reach the top of Everest, but who died on her way down. She finally got her chance and succeeded in 2000.
Lhakpa married the Romanian-American climber, George Dijmarescu, and the couple went on five Everest expeditions together in 2001, 2003, 2004, 2005, and 2006, before the marriage ended.
Her brother, Mingma Gelu Sherpa, said she was now confident of further success in her record-breaking ascent. "She's very strong and she never gives up," he told the Telegraph.