Alpine skiing, also known as downhill skiing, is a popular winter sport. It involves the use of skis while sliding down snow-covered mountains or hills. There are different types of ski trails and difficulty ratings, one of which is the double black diamond trail.
The double black diamond is the symbol used to designate very advanced ski trails. Its level of difficulty is rated as expert--only very advanced skiers should try it.
Double black diamond trails are very challenging. Its slopes are exceptionally steep, coupled with other hazards such as strong exposure to winds, narrow terrain and other difficult conditions.
Typically, double black diamond is rated as more than the 40 percent steep grade of the average black diamond ski slope, the ski level before it. This makes the double black diamond slope very steep and difficult to tackle.
Ski trail difficulty ratings in North America, from the lowest to highest level of difficulty, are green circle, blue square, black diamond and double black diamond.
As each ski resort determine its own terrain difficulty, there is no standard for every trail rating. The levels of all alpine trails are relative to each other. For example, a beginner level trail (green circle) at a steep ski mountain may be markedly more difficult than an intermediate level trail (blue square) at a vacation ski resort.