Ski tour^{Open in G4}

Going uphill or across a flat also requires grip, so that the ski will glide forward but not slide backwards when weighted. Dedicated cross-country touring skis may have a fish-scale pattern engraved into the base of the ski to enable the ski to grip, but most types of ski require the use of sticky wax or climbing skins for their smooth surface to grip. Skins are removable pieces of plush fabric whose nap runs at an oblique angle, allowing the ski to glide forward, but not back. Originally, these skins were actually made of furry seal skin.

If the snow is particularly icy or the skin track very steep, then the ski tourer may choose to attach ski crampons, sometimes called Harscheisen (German), couteau (French), or ramponi (Italian). Crampons are like knives that cut deeper into the snow.

As the slope angles increase, the climbing ski-tourer will make switchbacks, using so-called "kick turns" to change direction, typically resulting in a line that climbs at a moderate angle of 20-30 degrees. Skin tracks can be seen as zig-zags heading up a snowy mountain. Ski-tourers try to maintain the "up-tracks" in avalanche-safe zones as they head up the mountain, staying out from under dangerous cornices or slide paths. Setting a proper and safe skin track requires a great deal of skill and avalanche knowledge as the tourer spends most of their time climbing. Traveling quickly up the hill is important for safety as well. Thus physical fitness is one of the most important elements of safe mountain travel in potential avalanche terrain.

On reaching the summit or other intermediate destination, skins (if used) are removed and the skiers prepare to descend. In traditional cross-country skiing equipment and more robust telemark equipment, the skier's heel is also free on the descent, while AT skiers lock down their heels for the descent in typical alpine skiing style.

Ski touring requires the ability to ski off-piste, good navigation skills, and good awareness of the risks of the mountain environment in winter. In particular it requires the knowledge to assess and test snow conditions to minimise the risk of avalanche. Avalanche rescue equipment including radio transceiver, probe and shovel should be carried, and the ability to use them quickly and efficiently is required.

Additionally, ski mountaineering implies climbing a mountain with the intent of skiing it, often from the summit and/or down an elegant "line." Ski mountaineering blurs the line between mountaineering and skiing, as advocates typically choose peaks that are both worthy climbs and challenging descents. Ski mountaineering may require kicking in steps up steep sections while carrying the skis on a backpack. Ski mountaineers may also use ropes, ice axes and crampons for ascending slopes too steep for skinning or kicking steps. In some areas, ski mountaineering involves glacier travel, a whole subject unto itself. When skiing on glaciers it is wise for the party to wear harnesses, carry crevasse-rescue gear, and sometimes rope together to allow crevasse rescue techniques to be employed.

Equipment

All ski touring equipment has the common ability to free the heel for level and uphill travel. However ski touring can be carried out using a variety of equipment. The choice of equipment is determined by the ski touring goals and to some degree, the other types of skiing the individual participates in. Generally speaking, steeper, more difficult terrain requires a more supportive, heavier equipment choice:

Nordic

Nordic ski touring is skiing with bindings that leave the heels relatively free all the time. Thus, Nordic skiers do not have to change back and forth between uphill and downhill modes, which can be advantageous in rolling terrain.

Traditional Nordic

At the lighter, simpler end of the scale, Nordic skis may be narrow and edgeless cross-country types for groomed trails or ideal snow conditions, used with boots that resemble soft shoes or low boots.

These traditional Nordic skis have a "double-cambered" construction with a "wax pocket" to hold sticky wax under the foot for grip going uphill. Slicker "glide wax" is applied to the base of the ski in front of and behind the foot, for glide. The idea is for the ski's base to stick to the snow when the skier weights the ski going uphill, but glide along smoothly when the skier is on the flat or going downhill.

The most popular versions of these skis have bases with a grip pattern molded into the base under the foot, in a "fish scale" pattern, which can be used without kick wax. These "no-wax" skis are not as fast as waxable skis, but are more convenient to use and can perform better when the snow is at or very near the freezing point (0 degrees Celsius or 32 degrees Fahrenheit).

Either way, these traditional Nordic skis allow for very natural, seamless travel up and over mildly hilly terrain due to the lack of a need to change modes for ascending and descending.

The telemark turn was invented as a means of turning these lightweight skis with soft shoes that can't efficiently translate leg force to the ski.

Backcountry Nordic

There's also a mid-range solution. The backcountry Nordic ski is somewhat between traditional Nordic and Telemark. The ski's width at the tip can be anywhere from about 70 mm to around 90 mm, with the waist of the ski (the area underfoot) about 60 mm to 65 mm wide. Backcountry Nordic bindings designed for backcountry skiing are wider and more stout of construction, allowing more stability and better energy transfer between boot and ski. Many skiers use the 3-pin, 75 mm Nordic Norm or Telemark Norm boot/binding system for additional turning and speed control, even though it is somewhat slower than the newer NNN-BC (New Nordic Norm-Backcountry) binding "system." Backcountry Nordic boots are usually semi-rigid (usually the side is rigid), and the skis also have more carving "sidecut" similar to telemark/alpine skis, as well as metal edges. These features improve the skier's ability to turn and control their speed as slopes begin to get steeper.

Telemark

Like all Nordic boots, telemark boots flex at the toe for more natural walking and striding, but they are heavier and more supportive than other forms of Nordic ski boots. Telemark boots conform to the 75 mm Nordic norm, which provides for a duckbill at the front of the boot with 3 holes on the bottom. The soft soles of telemark boots make kicking steps or front pointing with crampons difficult.At the heavier end of the Nordic skiing equipment spectrum lie Telemark skis for steep backcountry terrain or ski-area use. These skis are similar to alpine skis and AT skis: heavier and wider than other Nordic skis with a smooth base and metal edges for carving turns in steeper terrain. Telemark gear, like AT equipment, is frequently used for ski touring because of the additional control the equipment provides on the descent. Like AT equipment, telemark equipment is heavier than other Nordic gear so the tourer is sacrificing the heavier weight on the uphill for ski ability on the descent.

Traditional "3 pin" telemark bindings clamp the duckbill with the 3 holes in the boots aligned with 3 pins on the bindings to provide rotational rigidity. Most modern bindings have a spring loaded cable that attaches around the heel of the boot, and most do away with the 3 pins entirely, since they tend to eventually shear out. The cable improves control, but can squeeze the arch of the foot painfully, so many cable attachment systems include a provision for relaxing the cable for climbs.

Telemark binding springs have become progressively stiffer to add downhill control by holding the ski tight to the bottom of the boot, but this also adds undesirable heel lift resistance when hiking. This added resistance makes ascending & traversing less efficient, especially when breaking trail through deep snow. Recent telemark binding designs add AT style free toe pivot with the addition of a catch that is released for hiking then locked for downhill skiing.

Telemark boots have gradually increased in stiffness and height to improve control. The increased forces have led to increasing desirability of releasable telemark bindings. However, the design constraints of the 75 mm Nordic norm do not allow the boot to release from the binding effectively. Instead, this type of releaseable telemark bindings leaves part of the binding attached to the boot when release occurs. New Tele Norm [NTN] is an emerging solution to the releasability problem that employs a plastic tab molded into the sole of the boot. This tab engages in a special binding that offers step-in convenience and releasability.

However, due to the physics of the problem, it is very difficult to design consistent release into a telemark binding, so there is currently no DIN-certified releasable telemark binding available. The free heel of Telemark equipment appears to help prevent knee injuries common to alpine skiers or AT skiers even without releasable bindings < http://www.ski-injury.com/nordic.htm>, but non-releasing bindings still present a serious hazard in avalanches where attached equipment creates drag that increases the possibility of injury and deeper burial—not a problem in ski resorts, but a serious consideration in the backcountry.

Alpine

Alpine Touring (randonnée)

Alpine Touring (AT) or randonnée equipment is specifically designed for ski touring in steep terrain. A special alpine touring binding is used that allows the heel to be clipped down for more support when skiing downhill, and allows it to be released to swing resistance-free from the toe when climbing. Like telemark gear, this equipment is popular with people from an alpine skiing background; unlike telemarking, it requires no learning of a challenging new type of downhill turn.

Most AT bindings have DIN safety release as in an alpine binding. Since the AT boot heel is locked for descending, the rigidity of the boot sole allows for reliable release and adds strength to the binding. This means that the bindings can be lighter in weight since they do not have to address the difficult physics of always-free-heel telemark bindings that place intense levering and twisting force on the toe piece. Some heavier AT bindings are also available and popular with users who cross over ski area boundaries and bring resort-style skiing with them, including jumping and high speed skiing, often using a heavier, more stable ski.

Special ski boots are also used, something of a cross between a downhill ski boot and a hiking boot, which are light and flexible enough to be comfortable to walk up in while still being stiff enough to provide good control when skiing down. These boots have specialized soles for traction and the ability to hold a crampon when climbing steep slopes with the skis on one's back.

Like downhill skiing boots, most AT Boots have rigid soles, which is advantageous for climbing steep snow slopes with or without crampons. However, all supportable ski boots—tele, AT or alpine—are less than comfortable for hiking approaches over bare ground, so most skiers will carry their ski boots & use a lightweight hiking or trail-running shoe when approaches are dry & it is not possible to drive to the snow.

Alpine Modified

Alpine skiing equipment can be used for ski touring with the addition of a removable binding insert that allows for free heel swing on ascents. The advantage of this set up is maximum support and safety release at higher speeds, in more difficult snow conditions and on steeper slopes as well as no new ski equipment needs other than the insert (assuming one already has alpine ski gear and avalanche rescue equipment).

The major downside of this equipment arrangement is that it is very heavy, stiff and uncomfortable on uphills and long traverses. Also, the wide, deeply side-cut skis currently popular for resort skiing are optimized for downhill turning and are less effective than narrower (by today's standards), straight sided skis for "survival" techniques sometimes used by ski tourers to cope with steep, difficult or unskiable snow conditions, for instance: jump-turns of various flavors, side-slipping, traversing, snowplowing, uphill herringbone and side-stepping.

Snowboard

Snowboard touring is a variation of the activity in which a snowboard is used for the descents. To ascend, the snowboard tourer removes the board and uses snowshoes, stubby skis or a snowboard that can split in two pieces lengthwise (splitboard) to be used like skis with skins on the ascent. Of course, with snowshoes or stubby skis the snowboard must be carried whilst ascending adding to the weight carried. Whereas a split board is more akin to skis and must be converted before the descent by removing the skins and fixing the two halves together.

Snowboards are the tool of choice for some difficult snow conditions like breakable crust, spring slush or dense new snow. Many people also prefer them for powder. Unfortunately, travelling over flats and uphill is somewhat contrived and difficult, with transitions taking much longer than skiers.