When talking about climbing, people who are not particularly familiar with the sport sometimes still assume that the sixth grade represents the highest level of difficulty a human being can climb. In my work, I often find myself talking about climbing, both with experienced climbers and with people who are just starting out. Especially among older generations, the idea that the sixth grade stands at the very top of the climbing scale is still surprisingly widespread.
To explore the idea of the sixth grade in greater depth, I wrote this short article to look at its origins and how its meaning has evolved over time.
There are several different grading systems used to describe the difficulty of a climb. When mountaineers plan a route in the mountains, they consult available descriptions and use the grades given in guidebooks to understand the level of difficulty they can expect. This information is essential, as it helps climbers choose routes suited to their abilities.
German mountaineer Willy Welzenbach was the first to codify climbing difficulties systematically, in 1925.
The Welzenbach scale and the limit of the sixth grade
Willy Welzenbach’s climbing grading system, known as the Welzenbach scale, originally consisted of six levels of increasing difficulty, from I (easy) to VI (the limit of human possibility). The choice of six grades appears to have been influenced by the six-point grading system used in German schools at the time. The system, easily recognisable by its use of Roman numerals, had one fundamental problem: it was a “closed” scale. The reluctance to extend it beyond VI stemmed largely from the belief that climbers had already reached the “limit of human possibility”.
As climbing techniques evolved, however, what had been classified as grade VI and appeared to represent the “human limit” in the 1930s and 1940s was far surpassed in the following decades by considerably more difficult climbs.
The Welzenbach grades, limited to VI, therefore became increasingly inconsistent and difficult to compare over time. As mountaineers opened harder and harder routes—routes to which we would now assign higher grades—they continued to be classified simply as VI. As a result, a route described as grade VI might in reality correspond to VII or even higher on the scale as we understand it today.
After considerable debate, the Welzenbach scale was eventually opened upwards by the UIAA (International Climbing and Mountaineering Federation). Today, the upper end of the UIAA scale reaches grade XII+, used to describe the difficulty of free climbing.
From grade IV upwards, intermediate grades can also be indicated using a plus (+) or minus (-), for example V+. It is worth remembering that the Welzenbach scale, now known as the UIAA scale, was originally developed specifically to grade rock climbs in the mountains. It is therefore not intended to describe ice climbing or aid climbing. Nor is it generally used for sport climbing at crags, although some countries also use the UIAA scale for sport routes.
Reinhold Messner played an important role in challenging the closed Welzenbach scale when, in 1974, his book The Seventh Grade: Most Extreme Climbing was published in English. As early as 1968, Messner had opened a difficult route on the Pilastro di Mezzo of Sass dla Crusc. The route included a short section of extreme difficulty, today graded UIAA VIII.
Messner, regarded at the time as one of the world’s finest mountaineers, criticised the Welzenbach grading system as irrational. The scale treated the sixth grade as the limit of human ability, yet once climbers began exceeding that limit, the system could no longer describe the true difficulty of their routes consistently.
Messner argued instead that the scale should remain open-ended, without any predetermined upper limit, and proposed a seventh grade to describe the greatest difficulties that the world’s best climbers were capable of overcoming at the time, in 1974.
The aim was to avoid devaluing earlier routes while allowing the grading system to reflect the continuing development of climbing standards. The seventh grade was officially introduced into the UIAA scale in 1978.
The UIAA climbing grade scale
| GRADE | DESCRIPTION |
|---|---|
| I | This is the simplest form of climbing: the hands are frequently used to maintain balance, and the quality of the rock should be assessed before placing weight on a foothold. |
| II | This is where climbing proper begins: you need to move one limb at a time, using the correct sequence of movements. Handholds and footholds are plentiful. |
| III | The rock becomes steeper, with fewer handholds and footholds, although there is still some choice of moves and possible lines. |
| IV | Handholds and footholds become smaller and less plentiful, and some technique is required to negotiate particular rock features such as chimneys, cracks and arêtes. |
| V | The climbing becomes more delicate and technical, particularly on slabs, and also requires physical strength on overhangs. The moves need to be studied before committing to them. |
| VI | It requires good physical fitness, experience and a solid level of technique. The climbing may be very delicate, requiring carefully planned sequences of moves, or demand considerable strength on overhanging walls. |
| VII | Handholds and footholds are generally small and sometimes widely spaced. Balance and technique are essential, together with specific training to develop considerable strength, including finger strength. |
| VIII - XII | From this point onwards, the difficulty continues to increase, now extending beyond UIAA X. At these grades, routes are unquestionably extremely difficult, with very small and often scarce handholds and footholds. Considerable endurance and strength in the fingers and arms are required, together with excellent climbing technique. UIAA XII is within the reach of only a very small number of climbers. Anyone climbing at this level is certainly among the best in the world. |
It is important to note, however, that although the UIAA scale is an international standard, many countries use different grading systems to describe climbing difficulty.
