Boskoff, 39, had summited six of the world’s 14 8,000-meter peaks — some, including Mount Everest, multiple times. In 1995, she summited her first 8,000-meter peak, Pakistan’s Broad Peak, alone and descended in the same storm that killed Alison Hargreaves, Rob Slater, and Jeff Lakes on neighboring K2. During her first Everest attempt, in 2000, she climbed to 7,900-meter Camp Four four times before the weather improved enough for her to summit. This feat led Boskoff ’s climbing partner Peter Habeler to remark, “Christine takes pain very well.”

In 1997, together with her late husband, Keith, Boskoff bought Mountain Madness, a guide service based in Seattle. As the business grew, she learned to balance personal climbing goals with the demands of running a company of 30-plus guides for which she was the public face. Boskoff often had a brutal, near-superhuman climbing schedule. For example, during the 2006 season, Boskoff led numerous trips in Colorado and Washington, went to Russia to guide Mount Elbrus, then off to lead a successful Cho Oyu climb, immediately followed by the two-month trip to China with Fowler (she was scheduled to guide Antarctica’s Mount Vinson in 2007). Like many full-time guides, Boskoff chose to spend her limited free time rock climbing.

Jane Courage, Boskoff’s best friend, introduced the pair to each other in 2000, and Boskoff and Fowler quickly found a common interest in visiting remote alpine objectives on a shoestring budget. In 2001, Boskoff set up the Colorado base for Mountain Madness two blocks over from Fowler’s house, in Norwood. Together, they climbed Shishapangma in 2000, and in 2002, the pair attempted a self-supported alpine-style ascent of the South Face of K2, turning around at 6,900 meters due to poor conditions. This effectively marked the end of Boskoff’s 8,000-meter career. (“Chris was far more amped to climb 6,000-ish-meter peaks that were unknown, somewhat remote, but [that] had great lines,” says Courage.) Indeed, in 2001, soon after they met, the duo attempted 6,250-meter Siguniang Shan in Sichuan and, though denied the summit due to poor snow conditions, were keen to return to the province.