1.
Cam
–
A cam is a rotating or sliding piece in a mechanical linkage used especially in transforming rotary motion into linear motion or vice versa. It is often a part of a wheel or shaft that strikes a lever at one or more points on its circular path. The cam can be seen as a device that rotates from circular to reciprocating motion, certain cams can be characterized by their displacement diagrams, which reflect the changing position a roller follower would make as the cam rotates about an axis. These diagrams relate angular position, usually in degrees, to the radial displacement experienced at that position, displacement diagrams are traditionally presented as graphs with non-negative values. A simple displacement diagram illustrates the follower motion at a constant velocity rise followed by a return with a dwell in between as depicted in figure 2. The rise is the motion of the follower away from the cam center, dwell is the motion where the follower is at rest, however, the most common type is in the valve actuators in internal combustion engines. Here, the cam profile is symmetric and at rotational speeds generally met with. Ideally, a curve between the onset and maximum position of lift reduces acceleration, but this requires impractically large shaft diameters relative to lift. Thus, in practice, the points at which lift begins and this is continuous with a tangent to the tip circle. In designing the cam, the lift and the dwell angle θ are given, here, the follower moves in a plane perpendicular to the axis of rotation of the camshaft. The base circle is the smallest circle that can be drawn to the cam profile, a once common, but now outdated, application of this type of cam was automatic machine tool programming cams. Each tool movement or operation was controlled directly by one or more cams, instructions for producing programming cams and cam generation data for the most common makes of machine were included in engineering references well into the modern CNC era. This type of cam is used in many simple electromechanical appliance controllers, such as dishwashers and clothes washing machines, a cylindrical cam or barrel cam is a cam in which the follower rides on the surface of a cylinder. In the most common type, the rides in a groove cut into the surface of a cylinder. These cams are principally used to convert rotational motion to linear motion parallel to the axis of the cylinder. A cylinder may have several grooves cut into the surface and drive several followers, applications include machine tool drives, such as reciprocating saws, and shift control barrels in sequential transmissions, such as on most modern motorcycles. A special case of cam is constant lead, where the position of the follower is linear with rotation. The purpose and detail of implementation influence whether this application is called a cam or a thread, but in some cases
2.
Ice axe
–
An ice axe is a multi-purpose hiking and climbing tool used by mountaineers both in the ascent and descent of routes that involve frozen conditions with snow and/or ice. An ice axe can be held and employed in a number of different ways, in its simplest role, the ice axe is used like a walking stick in the uphill hand, the mountaineer holding the head in the center, with the pick pointing to the rear. It can also be buried pick down, the rope tied around the shaft to form a secure anchor on which to bring up a second climber, or buried vertically to form a stomp belay. The adze is used to cut footsteps, as well as seats in the hillside. The long-handled alpenstock was a predecessor to the ice axe. The ice axe bears similarity in design to a war hammer. An ice axe is not only used as an aid to climbing, most ice axes meet design and manufacturing standards of organizations such as the Union Internationale des Associations dAlpinisme or European Committee for Standardization. There are two classifications of ice axe, Basic and Technical, Basic ice axes are designed for use in snow conditions for general mountaineering, and are adequate for basic support and self-arrest. Technical ice axes, which may have curved shafts, are enough to be used for steep or vertical ice climbing and belaying. An ice axe consists of at least five components, Head – usually made of steel and featuring a pick, a hole in the center is provided for attaching a wrist leash or carabiner. Pick – the toothed pointed end of the head, typically slightly curved, adze – the flat, wide end of the head used for chopping steps in hard snow and ice. Hammer – the hammer is an alternative to the adze for those traveling in softer snow and it can be used as a more comfortable grip, or as a striking hammer. Shaft – straight or slightly angled, typically wider front-to-back than side-to-side, flat on the sides, traditional shafts were made of wood, but are now almost exclusively of lightweight metals or composites. Spike, or ferrule – a steel point at the base of the used for balance. Common ice axe accessories include, Leash – nylon webbing with a loop for securing the axe to hand. Often secured by a ring constrained to slide a limited distance on the shaft, Leash stop – a rubber keeper or metal stud preventing the leash from slipping off of the ice axe. Snow basket – similar to baskets on ski poles, temporarily mounted on the close to the spike to keep the shaft from sinking into soft snow. Pick and adze guard – a cover to protect sharp edges
3.
Free climbing
–
Free climbing more specifically may include solo climbing, traditional climbing, sport climbing and bouldering. Free climbing should not be confused with aid climbing, in specific aid climbing equipment is also used to assist the climber in ascending the climb. The term free climbing originally meant free from aid, in lead climbing, a climber climbs a route from the ground up. For protection against a fall, the lead climber trails a rope which is managed by a belayer who remains on the ground or at an established anchor. As the leader climbs, they either place traditional protection such as cams and stoppers, or clip their rope through pre-placed bolted hangers or fixed anchors. The belayer feeds rope to the climber through a belay device, keeping a minimum amount of slack in the system. The leader climbs until the top is reached, and they can then belay the climber from above. Both climber and belayer attach the rope to their climbing harnesses, the rope is tied into the climbers harness with a figure-of-eight loop or double bowline knot. The leader either places their own protection or clips into permanent protection already attached to the rock, in traditional climbing, the protection generally is removable. However, many significant first ascents in the U. S. done with a combination of crack gear, usually nuts or spring-loaded camming devices are set in cracks in the rock. In sport climbing the protection is metal loops called hangers, hangers are secured to the rock with either expanding masonry bolts taken from the construction industry, or by placing glue-in bolt systems. In ice climbing the protection is made-up of ice screws or similar devices hammered or screwed into the ice by the leader, the lead climber typically connects the rope to the protection with carabiners or quickdraws. If the lead climber falls, they will fall twice the length of the rope from the last protection point, plus rope stretch, plus slack. If any of the breaks or pulls out of the rock or if the belayer fails to lock off the belay device immediately. Thus if a climber is 2 meters above the last protection they will fall 2 meters to the protection,2 meters below the protection, plus rope stretch and slack, if the leader falls, the belayer must arrest the rope to stop the fall. To achieve this the rope is run through a device attached to the belayers harness. The belay device runs the rope through a series of curves that. Some of the more types of belay devices are the ATC Belay Device
4.
Aid climbing
–
Aid climbing is a style of climbing in which standing on or pulling oneself up via devices attached to fixed or placed protection is used to make upward progress. In general, aid techniques are reserved for pitches where free climbing is difficult to impossible, while aid climbing places less emphasis on athletic fitness and raw strength than free climbing, the physical demands of hard aid climbing should not be underestimated. Aid climbing has its own ranking system, using a scale from A0 through A5. Just as in climbing, the usual aid technique involves two climbers, a leader and a belayer. The leader is connected by a rope to the belayer, who remains at the station while the leader moves up. As the leader advances, the rope is let out by the belayer, if the leader falls, the belayer locks off the rope and, assuming the protection doesnt pull out, catches the leaders fall on the rope. When the leader, moving up, reaches the end of the rope, or a convenient stopping point, he or she builds an anchor, hangs on it and this then becomes the next belay station. The belayer then ascends the rope using mechanical ascenders, retrieving the protection that was placed by the leader. Many variations on this technique are possible, including solo aid climbing and climbing with a team of three or more. Until the 1940s protection was provided by the piton, driven into a crack in the rock with a hammer, today, aid climbing uses a considerably larger array of hardware than the pitons used by the first climbers although the primary technique of ascension has not much evolved. The typical gear of an aid climber includes pitons, hooks, copperheads, nuts, camming devices, ascenders, hauling pulleys, aiders, daisy chains, the hardest aid routes are poorly protected requiring the climber to make long sequences of moves using hooks or tenuous placements. On these routes, a climber may have to commit to moving up onto the most marginal of placements risking long and sometimes dangerous falls. By contrast, the vast majority of aid ascents are done on popular free climbs which are too difficult for the aid party to free, but offer excellent gear placements. Since aid climbing is extremely slow compared to climbing, this can lead to some conflicts between aid climbers and free climbers waiting to climb a route. There is additional tension caused by the damage that aid climbing often does to routes, hooks frequently break or otherwise damage holds that human hands and feet do not. Until the 1960s or so, aid climbing was normal practice in most climbing areas, reinhold Messner wrote, Rock faces are no longer overcome by climbing skill, but are humbled, pitch by pitch, by methodical manual labour … Who has polluted the pure spring of mountaineering. Free climbing is now the mainstream of climbing, the solution is often a compromise in which an absolute minimum of bolts is added to allow safe protection for free climbers, while not totally destroying the challenge of the route as an aid climb. However, as with most compromises, this is not a solution that satisfies everyone, the A grading scale incorporates difficulty of placing protection, and the danger associated with falling
5.
Belaying
–
Belaying refers to a variety of techniques climbers use to exert tension on a climbing rope so that a falling climber does not fall very far. The term belay also means the place where the belayer is anchored, this is typically a ledge, but may be a hanging belay, where the belayer is suspended from protection in the rock. In a typical climbing situation, one end of the rope is fixed to the harness of the climber, using either a Rewoven Figure Eight, bowline, the rope then passes through climbing protection, which is fixed into the rock. Attachment to the rocks may be via bolts that are fixed into the rock, or by traditional protection that the climber places. The rope runs through the protection to a person called the belayer. The belayer wears a harness that has a device attached. The rope threads through the belay device, by altering the position of the end of the rope, the belayer can vary the amount of tension on the rope. In one position, the rope runs freely through the belay device, in another position, it can easily be held without moving, because the tension on the rope is so great. This is called locking off the rope, if the climber climbs three feet higher than the last piece of protection in the rock, and then falls, the rope allows him to fall the three feet to the protection, and another three feet below that. If they fall any further, rope is pulled upwards through the protection from the belayer below, because the belayer generally keeps the rope locked off, the climbers fall should be arrested and they are left suspended, but safe, somewhere below the protection. A dynamic rope, which has some stretch in it, is used so that the climber is not brought to a sudden jarring stop. Some climbers choose static ropes for abseiling/rapelling because its easier to use, while the task of belaying is typically assigned to a companion who stays at the bottom, self-belaying is also possible as an advanced technical climbing technique. The person climbing is said to be on belay when one of these methods is used. Belaying is a part of the climbing system. A correct belaying method lets the belayer hold the weight of the climber with relatively little force. By using a mixture of belaying angle and hand-grip on the rope, the belayer should keep the rope locked off in the belay device whenever the climber is not moving. As the climber moves on the climb, the belayer must make sure that the climber has the amount of rope by paying out or pulling in excess rope. If the climber falls, they free-fall the distance of the slack or unprotected rope before the friction applied by the belayer starts to slow their descent
6.
Prusik
–
A Prusik /ˈprʌsɪk/ is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, and by arborists. The term Prusik is a name for both the loops of cord and the hitch, and the verb is to prusik, more casually, the term is used for any friction hitch or device that can grab a rope. The word is misspelled as Prussik, Prussick or Prussic. The Prusik hitch is named after its inventor, Austrian mountaineer Karl Prusik. It was shown in a 1931 Austrian mountaineering manual for rope ascending, a prusik made from cord does little or no damage to the rope it is attached to, although some mechanical prusiks can cause damage, especially if the device slips during climbing. Climbers carry Prusik cords mainly for use, as they are lighter than other options. Prusiks are fast to place on a rope, and with practice can be placed one hand. The loops of cord can be used as slings, and are thus multi-functional in a climbing environment, Prusiks will work around two ropes, even two ropes of different diameters. Prusiks provide an attachment that will not damage or break the rope. Prusiks are good to use in hauling systems where multiple rope-grabs may be needed, Prusiks are far less likely to damage the main rope than mechanical rope-grabs such as a jumar. A prusik which is overloaded will initially slip, causing no damage, if loaded to great excess, the worst result is that it slides until the heat of friction causes physical failure of the prusik cord, rather than the rope. Mechanical rope-grabs when overloaded will sometimes damage the sheath of the rope, depending on which variant is used, Prusik hitches have the advantage of working in both directions. Most mechanical rope-grabs work like a ratchet, moving freely up the rope, traditional Prusiks will grab when pulled by the tail, either up or down, and will slide either way when pushed by the barrel. Although the Prusik Climb technique may be seen as outdated by some, rangers in the competition routinely make it up a 65-foot rope in under a minute. Prusiks are ineffective upon frozen wet ropes and this is due to the necessity of friction for the Prusik to function. Mechanical devices to grab the rope are available that are easier and faster to use, but heavier, more expensive, after being put under a great deal of weight, the Prusik can be quite constricted and difficult to untie. This varies, depending on the diameter of the ropes. Although prusik can be used in a way, the Prusik hitch is a specific hitch
7.
Caving
–
Caving — also traditionally known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland — is the recreational pastime of exploring wild cave systems. In contrast, speleology is the study of caves and the cave environment. Cave diving is a distinct, and more hazardous, sub-speciality undertaken by a minority of technically proficient cavers. Sometimes categorized as a sport, it is not commonly considered as such by long-time enthusiasts. Many caving skills overlap with those involved in canyoning, mine, Caving is often undertaken for the enjoyment of the outdoor activity or for physical exercise, as well as original exploration, similar to mountaineering or diving. Physical or biological science is also an important goal for some cavers, virgin cave systems comprise some of the last unexplored regions on Earth and much effort is put into trying to locate, enter and survey them. In well-explored regions, the most accessible caves have already been explored, Caving, in certain areas, has also been utilized as a form of eco and adventure tourism. Tour companies have established a leading and guiding tours into. Depending on the type of cave and the type of tour, in many areas, there are tours led through lava tubes by a guiding service. Some however consider the assistance cavers give each other as a team sport activity. Too much emphasis on the labeling of caving as a sport can narrow the goals of caving as a whole, Caving often puts the needs and welfare of a cave before those of the active participants. Clay Perry, an American caver of the 1940s, wrote about a group of men and this group referred to themselves as spelunkers, a term derived from the Latin spēlunca cave, cavern, den, itself from the Greek σπῆλυγξ spēlynks cave. This is regarded as the first use of the word in the Americas, throughout the 1950s, spelunking was the general term used for exploring caves in US English. It was used freely, without any positive or negative connotations, in the 1960s, the terms spelunking and spelunker began to be considered déclassé among experienced enthusiasts. This sentiment is exemplified by bumper stickers and T-shirts displayed by some cavers, Cavers rescue spelunkers, nevertheless, outside the caving community, spelunking and spelunkers predominately remain neutral terms referring to the practice and practitioners, without any respect to skill level. Potholing refers to the act of exploring potholes, a word originating in the north of England for predominantly vertical caves, the base term caving comes from the Latin cavea or caverna, meaning simply, a cave. He developed his own based on ropes and metallic ladders. Martel visited Kentucky and notably Mammoth Cave National Park in October 1912, robert de Joly, Guy de Lavaur and Norbert Casteret were prominent figures of that time, surveying mostly caves in Southwest France
8.
Reichenbach im Kandertal
–
Reichenbach im Kandertal is a village and municipality in the Frutigen-Niedersimmental administrative district in the canton of Bern in Switzerland. Until 1957 it was known as Reichenbach bei Frutigen, besides the village of Reichenbach, the municipality includes several other settlements, including Aris, Faltsche, Griesalp, Kien, Kiental, Ramslauenen, Reudlen, Scharnachtal, Schwandi and Wengi. Additionally, the village of Mülenen is shared between Reichenbach and Aeschi bei Spiez municipalities, the area played a notable role in world history when the Kienthal Conference was held at Kiental in 1916. The blazon of the coat of arms is Argent a Bear Paw issuant from a Mount of 3 Coupeaux Vert. Reichenbach im Kandertal is first mentioned about 1320 as Richenbach, during the Middle Ages, the village occupied a strategic location on the trade route into the Canton of Valais. Two castles, Mülenen Castle, with the Letzi Mülenen wall, a third castle, Faltschen Castle, may also be medieval, but this is not definitively known. The village was part of the Herrschaft of Mülenen, in 1352, Bern acquired the Herrschaft and with it the village. Originally Reichenbach was part of the parish of Aeschi bei Spiez, during the 15th century the chapel of St. Nicholas was built in the village. The chapel was first mentioned in 1453 and rebuilt in 1484, during the 18th and 19th centuries it was renovated and expanded. After Bern accepted the Protestant Reformation, Reichenbach converted to the new faith in 1529, a filial church was established in the village of Kiental in 1929, while Wengi and Schwandi are still part of the Frutigen parish. Traditionally the villages lived from farming and seasonal alpine herding as well as some trade over the mountain pass, beginning in the 16th century, the local farmers began raising cattle for export. In 1865 a match factory opened in the area. The post carriage began operating between Reichenbach and Thun in 1814, in 1901 a railroad was completed that linked the municipality with Spiez. This was followed by the Niesen train in 1910 and the Bern-Lötschberg-Simplon Railway in 1913, the new transportation links quickly changed Reichenbach into a tourist destination. The population grew and many homes were built in the municipality. A military airport was built in the valley, but in 1994 it switched to a civilian airport. A secondary school was built in 1959-60, the Kienthal Conference was held in Kiental between 24 and 30 April 1916. On 31 December 2009 Amtsbezirk Frutigen, the former district, was dissolved
9.
Climbing
–
Climbing is the activity of using ones hands, feet, or any other part of the body to ascend a steep object. It is done recreationally, competitively, in trades that rely on it and it is done indoors and out, on natural and manmade structures. Climbing activities include, Bouldering, Ascending boulders or small outcrops, often with climbing shoes, canyoneering, Climbing along canyons for sport or recreation. Chalk climbing, Ascending chalk cliffs uses some of the techniques as ice climbing. Competition Climbing, A formal, competitive sport of recent origins, competition Climbing has three major disciplines, Lead, Bouldering and Speed. Ice climbing, Ascending ice or hard snow formations using special equipment, usually ice axes, techniques of protecting the climber are similar to those of rock climbing, with protective devices adapted to frozen conditions. Indoor climbing, Top roping, lead climbing, and bouldering artificial walls with bolted holds in a climbing gym, mountaineering, Ascending mountains for sport or recreation. It often involves rock and/or ice climbing, pole climbing, Climbing poles and masts without equipment. Lumberjack tree-trimming and competitive tree-trunk or pole climbing for speed using spikes, rock climbing, Ascending rock formations, often using climbing shoes and a chalk bag. Equipment such as ropes, bolts, nuts, hexes and camming devices are normally employed, rope access, Industrial climbing, usually abseiling, as an alternative to scaffolding for short works on exposed structures. Rope climbing, Climbing a short, thick rope for speed, not to be confused with roped climbing, as in rock or ice climbing. Scrambling which includes rock climbing, and is considered part of hillwalking. Sport climbing is a form of climbing that relies on permanent anchors fixed to the rock. Top roping, Ascending a rock climbing route protected by a rope anchored at the top and protected by a belayer below Traditional climbing is a form of climbing without fixed anchors and bolts. Climbers place removable protection such as camming devices, nuts, free solo climbing, Climbing without ropes or protection. Tree climbing, Recreationally ascending trees using ropes and other protective equipment, a tower climber is a professional who climbs broadcasting or telecommunication towers or masts for maintenance or repair. Rock, ice and tree climbing all usually use ropes for safety or aid, pole climbing and rope climbing were among the first exercises to be included in the origins of modern gymnastics in the late 18th century and early 19th century
10.
Bouldering
–
Bouldering is a form of rock climbing that is performed without the use of ropes or harnesses. While it can be done without any equipment whatsoever, most climbers use climbing shoes to help secure footholds, chalk to keep their hands dry, unlike free solo climbing, which is also performed without ropes, bouldering problems are usually less than 6 meters tall. Artificial climbing walls allow boulderers to train indoors in areas without natural boulders, Bouldering competitions, which employ a variety of formats, take place in both indoor and outdoor settings. The sport originated as a method of training for roped climbs, Bouldering enabled climbers to practice specific moves at a safe distance from the ground. Additionally, the served to build stamina and increase finger strength. Throughout the 1900s, bouldering evolved into a separate discipline, individual problems are assigned ratings based on their difficulty. There have been many different rating systems used throughout the history of the sport, the growing popularity of the sport has caused several environmental concerns, including soil erosion and trampled vegetation as climbers hike off-trail to reach bouldering sites. This has caused some landowners to access or prohibit bouldering altogether. Unlike top rope climbing and lead climbing, no ropes are used to protect or aid the climber, Bouldering routes or problems require the climber to reach the top of a boulder, usually from a specified start position. Some boulder problems, known as traverses, require the climber to climb horizontally from one position to another, the characteristics of boulder problems depend largely on the type of rock being climbed. Granite, for example, often features long cracks and slabs, sandstone rocks are known for their steep overhangs and frequent horizontal breaks. Other common bouldering rocks include limestone and volcanic rock, there are many prominent bouldering areas throughout the United States, including Hueco Tanks in Texas, Mount Evans in Colorado, and The Buttermilks in Bishop, California. Squamish, British Columbia is one of the most popular bouldering areas in Canada, Europe also hosts a number of bouldering sites, such as Fontainebleau in France, Albarracín in Spain, and various mountains throughout Switzerland. Artificial climbing walls are used to simulate boulder problems in an indoor environment and these walls are constructed with wooden panels, polymer cement panels, concrete shells, or precast molds of actual rock walls. Holds, usually made of plastic, are bolted onto the wall to create problems. The walls often feature steep overhanging surfaces, forcing the climber to employ highly technical movements while supporting much of their weight with their body strength. Climbing gyms often feature multiple problems within the section of wall. Across much of the rest of the problems and grades are usually designated by using a set color of plastic hold to indicate a particular problem
11.
Free solo climbing
–
Unlike in bouldering, free soloists typically climb above safe heights, where a fall would always result in serious injury or death. In ordinary free climbing, safety gear is used to protect from falls, other reasons given are the intense concentration required and, for some, the adrenaline rush. The practice is confined to routes familiar to the climber. However, inherent risks such as rocks or sudden change in weather are always present. The sport has produced a number of practitioners, made famous by photos of a climber totally alone. Two of the most famous free soloists, Alain Robert, and Dan Goodwin, have also scaled dozens of skyscrapers around the world — a sport known as buildering —, there are few climbers who have free solo climbed in the 5.14 range. This list does not include highball boulder ascents because the climbers here did not use any padding or spotters, there is some debate on the blurred line between highball bouldering and short free solo climbs. 5. 14b - Darwin Dixit - Margalef, Spain - Dave MacLeod,5. 14a - Kommunist - Tyrol, Austria - Alexander Huber,2004. Paul Preuss died during an attempt to make the first ascent of the North Ridge of the Mandlkogel free solo, tobin Sorenson died from a fall during a solo attempt of the Mount Albertas North Face. Jimmy Jewell fell to his death from Poor Mans Peuterey at Tremadog, ironically, he was using the route as a shortcut from a local pub to his climbing club hut, the route was well below his usual grade and capability. Derek Hersey died in an accident while soloing the Steck-Salathé Route free solo, dwight Bishop fell climbing alone and unroped, Wyoming, Grand Teton National Park, The Grand Traverse. Jimmy Ray Forester fell while free-soloing in El Potrero Chico, Mexico, Forester, an experienced, talented climber, failed to return to camp after setting out on The Scariest Ride in the Park, a 40-pitch 5.9 ridge route known for loose rock. He was found the day at the base of the wall. George Gardner fell to his death while free soloing in Grand Teton National Park, John Bachar died in a free solo accident at Dike Wall near Mammoth Lakes, California. Akihira Tawara died while free climbing the Directissima 5.8 route on Yamnuska. Michael Ybarra died climbing solo on The Matterhorn Peak in Californias Sierra Nevada Mountains, brad Parker fell about 300 feet to his death while attempting to climb Matthes Crest Traverse in Yosemite, CA. Andrew Barnes died falling 50 ft free solo climbing in New Yorks Shawangunk Mountains. Angus Moloney died falling 100 ft free-solo climbing from the Fifth Pinnacle above the Gregory Canyon Trail, Boulders Open Space, alternatives to free soloing include, Free climbing with the use of ropes to prevent a fall. Bouldering, climbing at heights low enough that a fall would normally be safe, deep water soloing, climbing over a body of water
12.
Climbing wall
–
A climbing wall is an artificially constructed wall with grips for hands and feet, usually used for indoor climbing, but sometimes located outdoors. Some are brick or wooden constructions, but on most modern walls, recently, manufactured steel and aluminum have also been used. The wall may have places to attach belay ropes, but may also be used to lead climbing or bouldering. Each hole contains a specially formed t-nut to allow modular climbing holds to be screwed onto the wall, with manufactured steel or aluminum walls, an engineered industrial fastener is used to secure climbing holds. The face of the multiplex board climbing surface is covered with textured products including concrete, in addition to the textured surface and hand holds, the wall may contain surface structures such as indentions and protrusions, or take the form of an overhang, underhang or crack. Some grips are formed to mimic the conditions of outdoor rock, including some that are oversized, the earliest artificial climbing walls were typically small concrete faces with protrusions made of medium-sized rocks for hand holds. Schurman Rock in Seattle, WA is believed to be the first artificial climbing structure in the United States, the modern artificial climbing wall began in the UK. The first wall was created in 1964 by Don Robinson, a lecturer in Physical Education by inserting pieces of rock into a corridor wall, the first commercial wall was built in Sheffield, traditionally Englands centre for climbing due to its proximity to the Peak District. The first indoor climbing gym in the U. S. was established by Vertical World in Seattle, the simplest type of wall is of plywood construction, known colloquially in the climbing community as a woody, with a combination of either bolt-on holds or screw on holds. Bolt-on holds are fixed to a wall with iron bolts which are inserted through the hold, which will have specific bolt points, screw-on holds are, by contrast, usually much smaller, owing to the nature of their fixing. These holds are connected to the wall by screws which may be fastened anywhere on the walls surface, holds come in different colours, those of the same colour often being used to denote a route, allowing routes of different difficulty levels to be overlaid on one another. Coloured tape placed under climbing holds is another way that is used to mark different climbing routes. The grade of the route is usually a decision between the setter of the route and the first few people who climb the route. Many indoor climbing walls have people who are assigned to set these different climbing routes and these people are called route setters or course setters. As indoor climbing walls are used to check the development of climbers ability. Climbing Indoor climbing UK Climbing Wall Manufacturers Association Climbing Wall Association, a US non-profit, industry trade association
