free solo climbing or free soloing, is a form of technical ice or rock climbing where the climbers (or "free soloists") climb alone without ropes, harnesses or other protective equipment, forcing them to rely entirely on their own individual strength and skill. free soloing is the most dangerous form of climbing, and unlike bouldering, free soloists climb above safe heights, where a fall would result in serious injury or death. though many climbers have attempted free soloing, it is considered "a niche of a niche" reserved for the sport's elite, which has led many practitioners to stardom within both the media and the sport of rock climbing. "free solo" was originally a term of climber slang, but after the popularity of the oscar-winning film "free solo", merriam-webster officially added the word to the english dictionary in september 2019.