Several times, the expedition came close to failure. After a long acclimatization process, including a month spent exploring a lower-elevation mountain nearby, the team finally approached the summit of Llullaillaco after establishing a series of camps throughout the ascent. Throughout this expedition, the researchers braved severe winds of over and extreme temperatures, at one point reaching . At their final camp, at an elevation of , a storm broke and lasted for four days. According to Reinhard, the team [was] about to give up when they spotted an artificial layer in the site that indicated they should continue the investigation. The researchers followed the artificial layer, which eventually led them to the burial of one of the mummies.