Crampons are outdoor footwear that are made from spikes and are worn on boots to provide traction on snow and
ice. General-purpose crampons designed for most
mountaineering and
glacier travel are not well suited for vertical
ice climbing. For ice climbing, specialized crampons that provide better support for
front pointing are advised. Most crampons require
welted boots to ensure proper fitting.
Crampons with 10 points were first introduced by Europeans in the early 1900s. Because they lacked forward pointing spikes, they required step cutting on steep terrain. In the 1930s, two additional forward-slanting points were added, thus creating today's 12-point crampons. While 12-point crampons are now the normal selection, a few 10 point crampons can still be found on the market. The two additional front points further reduced step-chopping and allowed the climber to "front-point" up steep snow and ice. The angles of the first two rows of points also determine the best use for a particular set of crampons. If the first row (front points) bend downward and the second row is angled towards the toe, this reduces calf strain by allowing the boot heel to be lower. In this case, these crampons are better suited for front-pointing. When straight points are used instead, the crampons are much better suited for snow & general mountaineering.
While crampons are an invaluable tool for a mountaineer, they were not used as often as today until the development of plastic-shelled climbing boots, because the straps used to affix the crampons to early mountaineering boots (which were made of leather) had a tendency to restrict bloodflow to the feet of the wearer.
Crampons are usually made of hardened steel, but lighter weight aluminum crampons are popular for alpine ski touring where the need for them is less frequent & counterbalanced by the need for a light pack yielding fast, efficient travel over long distances.