After their first trip to the Himalaya and subsequent labor problems, the Workmans hired Matthias Zurbriggen, the best and most experienced mountain climbing guide of the time. Thus, in 1899, with 50 local porters and Zurbriggen, the Workmans began to explore the Biafo Glacier in the Karakoram, but dangerous crevasses and poor weather forced them instead to shift to the Skoro La Glacier and the unclimbed peaks around it. They reached Siegfriedhorn, an 18,600-foot (5,700 m) summit that she named after her son, giving Fanny an altitude record for women at the time. They next camped at and climbed a higher peak of , naming it Mount Bullock Workman. Admiring the view of a far-off mountain, they commented on the grand view: they were looking at K2, the second-highest mountain in the world. Fanny Workman may have been the first woman recorded to have seen it. Finally, they climbed Koser Gunge (), giving Fanny her third successive altitude record. It was very challenging: they had to hire new porters, establish a new base camp, and remain overnight at around . In the morning, they climbed a wall that measured , and were buffeted by winds. During the summit push, Fanny's fingers were so numb that she could no longer hold her ice ax and one of the porters abandoned them. Pauly writes, propelled to the summit by adrenalin and desperation, the foursome lingered only long enough for their instruments to assess that the temperature was ten degrees Fahrenheit [−12 °C] and their elevation was 21,000 feet. Fanny was a slow, relentless, and intrepid climber; bearlike, she solidly planted one foot and then groped for another secure grip with the other. Climbing at the beginning of the 20th century, she did not have specialized equipment like pitons or carabiners. She was able to climb to such heights, Pauly argues, because of her dauntless persistence and her immunity to altitude sickness.