Yosemite Decimal System
The Yosemite Decimal System is a scale for rating the difficulty of trails and climbing routes. The Wikipedia description may be found here. The exact definitions of each of the classes are not fully agreed upon, but the general canyoneering interpretation is included below.
YDS classes
- Class 1: Easy, well-maintained trails
- Class 2: Rougher trails where hands are sometimes needed to steady oneself
- Class 3: Scrambling where handholds are necessary to make progress, most people face away from the rock while descending
- Class 4: Hard scrambling or simple climbing, most people face toward the rock to descend
- Class 5: True rock climbing. This class is subdivided into 5.1, 5.2, etc. When originally developed, 5.9 was supposed to be the hardest climb a human could manage. Many advances have been made since then, however, and the scale has expanded by incrementing the second number all the way up to 5.15 currently.
- Class 6: Cannot be climbed without aid tools; they are required to make progress
Issues
One of the main difficulties of the YDS system is that it attempts to rate based both on difficulty and exposure. Therefore, it is difficult to decide what class should be assigned to something which is easy but has extreme exposure (Angel's Landing, for instance), or what class should be assigned to something which is difficult but has very little exposure. Canyoneering usage tends to favor difficulty over exposure when choosing a descriptive class, and then noting "exposed" if the route or maneuver has notable exposure.
External links
- Climber.org description
- Colorado Mountaineering guide (with pictures)
