thumb|upright=1.2|Various [[alpine climbing routes highlighted in colour on the north face of Les Droites in the Alps]]

A climbing route () is a path by which a climber reaches the top of a mountain, a rock-face, or an ice-covered obstacle. Climbing routes are recorded in a climbing guidebooks and/or in online climbing-route databases. Details recorded include the type of climbing route (e.g. bouldering route, sport climbing route, traditional climbing route, ice climbing route, or alpine climbing route, etc.), the difficulty grade of the route–and the beta for its crux(es)–including any risk or commitment-grade, the length and number of pitches of the route, and the climbing equipment (e.g. climbing protection gear) that is needed to complete the route.

Definitions have been agreed on what determines a valid ascent of a route (e.g. the redpoint in rock climbing), and on the classes or styles of ascent (e.g. onsighted, flashed). The coveted first ascent (FA), first free ascent (FFA), and first female free ascent (FFFA), are chronicled for most routes. After a route is established, variations can be created (e.g. directessimas, sit starts, or enchainments), and climbers will try to improve on the style in which the route is climbed (e.g. minimizing aid climbing or removing other supports such as oxygen or fixed ropes). Some climbers will try to reduce or limit the in-situ climbing protection (e.g. greenpointing) or will try to completely free-solo the route. Others seek to set speed climbing records on routes.

The ascent of ever-harder routes is an integral key part of the history of climbing, and each type of climbing has notable routes that set major new milestones of difficulty. There are ongoing debates amongst climbers about routes including the naming of routes, the creation of new routes by artificially altering the surface (e.g. chipping in rock climbing), the role of completely artificial indoor routes (e.g. The Project), the level and maintenance of in-situ climbing protection on routes (e.g. providing permanent bolted protection anchors) and the ethical issue of retro-bolting (e.g. turning traditional climbing routes into safer sport climbing bolted routes).

Details recorded

thumb|"[[Topo (climbing)|Topo" of a multi-pitch alpine climbing route on the SW Pillar of the (500-metres, grade TD)]]

Climbing routes are usually chronicled in a climbing guidebook, a climbing journal (e.g. the American Alpine Journal or the Himalayan Journal), and/or in an online route database (e.g. theCrag.com or MountainProject.com), where the key details of the route are listed, such as:

Physical details

  • Climbing area (or crag). Routes are often clustered together in a general "climbing area", which is also known as a "crag". Notable climbing areas include: El Capitan (for big wall climbing in the US), Clogwyn Du'r Arddu (for traditional climbing in the UK), Buoux, Verdon Gorge and Ceuse (for sport climbing in France). In countries such as France the person who created the route names it, whereas in others such as the US and UK, the first person to ascend the route names it (e.g. the Realization/Biographie controversy). Alpine routes tend to have names based on the peak or the first ascender and the geological feature, such as the Bonatti Pillar or the Walker Spur.
  • Length and number of pitches. A key detail is the length of the route, which can vary from a few metres for a bouldering route, to several thousand metres for a big wall climbing or alpine climbing route. Longer routes are broken up into "pitches", which are less than a rope length; climbers will lead each pitch one at a time. For example, The Nose is over 880-metres long, and breaks up into 31-pitches.
  • Crack climbing, are routes following a system of crack(s) that the climber uses to ascend the route; the width of the crack dictates the techniques needed, and crack-climbs are further differentiated by the body parts that can be 'jammed' into them.
  • Face climbing, where the rock face is fully vertical, unlike in slab climbing, and is largely featureless, unlike in crack climbing; face-climbing routes are typically sustained and exposed, and longer multi-pitch routes can become big wall climbing.
  • Overhang (or roof) climbing, where the rock face leans back at an angle of over 90 degrees for part or all of the climb, and at its most severe can be a horizontal roof; most of the hardest modern climbs are continuously overhanging.

After the first ascent, climbers will look to ascend via the main ridges and the main faces of the mountain. While face-routes are typically more severe due to their greater steepness, there are many notable ridge-routes that are equally serious undertakings due to their length and complexity (e.g., Everest's North East Ridge, Nanga Parbat's Mazeno Ridge or the Compressor Route on Cerro Torre's South East Ridge ). Climbers will also look to climb prominent features on the faces such as couloirs (e.g., the SuperCouloir), and ribs, spurs or pillars of rock (e.g., the Bonatti Pillar or the Walker Spur).

North-face routes are often the most challenging as their northerly aspect means that that they are more ice-covered and avalanche prone all year round, and they are hit by more serious weather systems than the other faces (e.g, the famous 1938 Heckmair Route on the Eiger). The Great north faces of the Alps are considered major testpiece routes for aspiring alpine climbers. All major climbing peaks will have many routes on all of their main faces, some following different crack systems or physical features, and others being harder technical refinements and variations of earlier routes.

For variations of routes

When a rock climbing or mountaineering route has been established, variations may be subsequently added, a typical one being a more "direct" line (e.g. a direct start or direct finish) of the original route, also called a direttissima in alpine climbing, and thus not avoiding the difficult obstacles that the original route went around (e.g. a roof or an overhang, or a section with minimal holds). Boulder climbers might add a harder sit start "SS" (or sit-down-start, "SDS") variation to a boulder route (e.g. the SDS of Dreamtime is graded well above the standing start version). Alpine and big wall climbers often seek to link established routes together in a larger enchainment (or "link-up") route (e.g. the notable Moonwalk Traverse of the entire Cerro Chaltén Group in Patagonia).

For types of ascents

The definition of what is classed as a valid ascent of a climbing route is a redpoint. Alpine climbers distinguish whether the ascent was made in summer or in the more difficult winter season (e.g. it was not until 2021 that K2 was climbed in winter).

thumb|[[Alex Honnold's 2017 free solo of Freerider (5.13a, 7c+), El Capitan]]

Climbers will also seek to improve the "style" in which a route is climbed. A route that uses a lot of aid climbing will be reclimbed with less and less aid until it is eventually "free climbed" (i.e. using no aid, either as a sport or a traditional climb). Alpine climbers seek to complete established high-altitude "expedition style" routes in alpine style with no supplemental oxygen or any fixed ropes, and even alone. Free solo climbers seek to ascend a route with no protection equipment whatsoever (e.g. as in the 2018 film, Free Solo). Some big wall climbers set speed records on routes (e.g. The Nose).

Debates about routes

Naming of routes

Traditionally, in many countries, the person who made the first ascent of a route was allowed to name it (in France, the naming rights go to whoever first bolted the route);

In 2020, the climbing community more directly confronted the issue of problematic names. In June 2020, climbing author Andrew Bisharat wrote in Rock & Ice that "routes belong to us all. That should include their names" in regard to changing problematic names. At the same time, Duane Raleigh, the editor of Rock & Ice, stepped down from his post recognizing some problematic names that he had given his own routes in the past. and was described as climbing's "#MeToo" moment.

In 2021, the American Alpine Club created the "Climb United" initiative to bring magazine editors, guidebook publishers and database managers, and other climbing community leaders together to create principles for naming routes that would "Build the best publishing practices to avoid harm caused by discriminatory or oppressive route names". Many climbing guidebook publishers and route databases introduced policies to redact inappropriate route names, including the largest online databases, theCrag.com,

Manufactured or artificial routes

Some climbers have physically altered the natural rock surface to "construct" a route (or make a route more climbable), by cutting or expanding handholds, which is also known as chipping. Such acts have at times caused controversy (e.g. Fred Rouhling's Akira and Hugh), but at other times has not (e.g. 's famous Buoux route, La Rose et la Vampire). A 2022 survey by Climbing showed climbers were largely against manufacturing routes on natural outdoor rock on public lands, but were less negative on private lands (or on routes in quarries); they were willing to allow "cleaning" of routes (which some consider manufacturing), and also the repairing of routes (e.g. gluing back broken holds). In 2017, Black Diamond Equipment launched "The Project" on an indoor climbing wall in Sweden, with the aim of creating the world's hardest sport climbing route at circa. ; it was later deconstructed having never been fully ascended, despite attempts by some of the world's best climbers, including Adam Ondra, Stefano Ghisolfi, and Alex Megos.

Permanent-protection and retro-bolting of routes

thumb|In-situ sport climbing protection with a [[dynamic rope|rope clipped into a quickdraw that is clipped into a fixed climbing bolt.]]

There has been a long-term debate in the climbing world on the use of permanently fixed in-situ climbing protection (e.g. such as bolts or pitons) on climbing routes.

Other objections to pre-bolted protection highlighted the effect that such protection had on the very nature and challenge of a climbing route. Such concerns also relate to the debate on retro-bolting of traditional climbing routes, which is the conversion into safer sport climbing routes, but that also fundamentally alters the nature of the route challenge.

Notable routes

Rock climbing

  • Bouldering. Two of the most famous bouldering routes in history are Midnight Lightning in California, and Dreamtime in Switzerland. Other notable bouldering routes include ' in Italy, the world's first-ever graded route, and Burden of Dreams in Finland, the world's first-ever graded route.
  • Sport climbing. Two of the most famous sport climbing routes in history are Action Directe in Germany, the world's first-ever route, and Realization/Biographie in France, the world's first consensus route.
  • Traditional climbing. Traditional climbing was at the origin of free climbing, and many countries have their own notable traditional routes (e.g. Indian Face in Britain). Routes that set important milestones include Grand Illusion in Lake Tahoe, first , The Phoenix in Yosemite, first and the first-ever use of "friends", and Super Crack in the Shawangunks, early consensus . Notable contemporary traditional climbing routes include Cobra Crack in Canada, Rhapsody in Britain, Blackbeard’s Tears and Meltdown in the US, and Tribe in Italy.
  • Big wall climbing and aid climbing. Many of the most famous aid climbing routes were on big wall routes, which eventually became free climbing routes. The most famous route is The Nose whose aid ascent at 5.9 A2 was a major milestone in climbing, as was its eventual freeing at 5.14a. El Capitan has several other famous aid/big wall routes such as Salathé Wall (5.9 A2 aid, or 5.13b free) and the Salathé variant, Freerider, the most famous big wall free solo in history, and Dawn Wall, the first-ever 9a big wall route in history.

Ice climbing

  • Ice climbing. Notable ice routes include the first to get near/above the WI6 grade milestone (i.e. sheer vertical sustained ice) such as Gimme Shelter, Riptide, and Sea of Vapours in the Canadian Rockies, Since 2010, Helmcken Falls in Canada has produced overhanging ice climbs above the WI10 grade, including Mission to Mars the world's first-ever WI13 graded ice route.
  • Mixed climbing. The most famous route is Jeff Lowe's Octopussy WI6 M8 R, which started the mixed climbing revolution; this was followed by early consensus M10-12 routes in Europe and North America such as Reptile in Vail, Colorado, X-files and Empire Strikes Back in Val di Cogne, and Musashi in Canada. Iron Man in Switzerland became the world's first consensus M14, and also the world's first-ever FFFA of an M14.
  • Dry tooling. Notable routes include Bichette Light in France, the world's first-ever D14 (and with no mixed/ice component). The Tomorrow's World Cave in the Dolomites in Italy produced the world's first-ever consensus D15 (A Line Above the Sky), and consensus D16 (Parallel World) routes.

Mountaineering

  • Alpine climbing. One of the most famous alpine climbing routes is the 1938 Heckmair Route (ED2 V− A0 60 degrees), on the north face of the Eiger. The route is also one of the famous six alpine routes that first ascended the great north faces of the Alps. As alpine climbing spread outside of the Alps, famous alpine style routes were established on Himalayan peaks such as Latok I, The Ogre, Changabang, and Jannu.