Mixed climbing

Mixed climbing is an ice climbing discipline used on climbing routes that do not have enough ice to be regular ice climbs, but are also not dry enough to be regular rock climbs. To ascend the route, the mixed-climber uses normal ice-climbing equipment throughout (e.g. double ice tools or ice axes in their hands, and crampons on their feet), but to protect the route, they use both ice and rock equipment. Mixed climbing varies from routes with sections of thick layers of ice interspersed with sections of bare rock, to routes that are mostly rock but which are "iced-up" in a thin layer of ice and/or snow.

While alpinists have used mixed climbing techniques for decades on alpine routes (most north-facing alpine routes are iced or snow-covered), mixed climbing as a standalone sport came to wider prominence with Jeff Lowe's ascent of the partially bolted Octopussy (WI6, M8 R) in 1994. Mixed climbing also led to the sport of dry-tooling, which is mixed climbing on routes that are completely free of all ice or snow. The equipment used — the lengths of ice tools and the use of heel spurs and ice axe leashes — has become more regulated to avoid concerns of being more like aid climbing than free climbing.

Mixed climbing routes are graded for difficulty on an M-grade system, and the development of specialized mixed climbing techniques (e.g. stein pulls and figure-four moves), and specialised equipment (e.g. fruit boots, heel spurs, and advanced ergo ice axes), led to dramatic increases in mixed climbing grade milestones, particularly from 1994 to 2003, and have also been credited with pushing standards in the wider field of alpine climbing. Many modern mixed routes are now bolted like sport climbing routes, but some mixed climbing routes still use traditional climbing-type protection—particularly on multi-pitch routes.