North American Ski Trail Rating System: A Guide to Terrain Difficulty

How are Trails Ranked?

Have you ever found yourself in a ski resort, going down a certain run, thinking to yourself, how these resorts dictate what difficulty level a run should be? Many people assume it's based on opinion, with certain runs at some resorts feeling harder or easier than the same difficulty level at another resort they've been to. The truth is, it isn't just based on opinion; U.S. ski resorts all follow the same general criteria when rating a ski trail's difficulty.

Types of runs you'll find at North American resorts:

1. Green Circle (beginner run)

2. Blue Square (intermediate run)

3. Black Diamond (advanced run)

4. Double Black (expert terrain)

5. Triple Black (unofficial, extreme terrain)

The runs are rated upon these three general criteria:

1. The steepness of the run (Gradient)

2. The width of the run

3. Terrain Features (Hazards)

Steepness (Gradient):

The steepness of the run is generally one of the most important features of the trail that dictates its level, as runs that have a grade of 6-25% are rated as Green Circle (beginner) runs, 25-40% are Blue Square (intermediate), and Black Diamond (expert) are 40%+ grade. This is typically the steepness criterion that resorts follow, as steepness is a major factor in how difficult a trail can be.

Width:

The width of the terrain is also something that is considered when trails are being rated. Black diamond double black runs typically run more narrow than blues and greens. This is because it's harder to navigate these runs due to their condensed nature. However, some easier runs, like green and blues, may have narrow sections, which aren't always taken into consideration, especially when other parts of the trail are wider.

Terrain Features (Hazards):

This is the main determinant when it comes to whether or not a run is intermediate, advanced, or expert. These hazards can include moguls, rocks, trees, foliage, and even cliffs/drop-offs. Some of the most extreme runs have almost all of these hazards. As opposed to green and blue runs, where there are typically no hazards whatsoever. Hazards can become more extreme when coupled with width and steepness. Many double black runs in North America, such as chutes, are a combination of these factors.

This truly changes a ski run from a simple powdery slope into a truly challenging and even potentially fatal rapid descent with multiple hazards that need to be addressed. Many skiers and snowboarders who have skied for many years, or simply have just reached a high skill level of skiing or snowboarding, can tackle these runs without relative success.

Conclusion...

Ski trails are an extremely difficult thing to rate if you think about it. With how diverse the mountains and overall terrain are, there isn't a one-size-fits-all rating for a ski slope. Thats why a green run at one resort can be entirely different in terms of difficulty than a green run at another resort. Despite that fact, all ski runs in North America are ranked based off their gradient, width, and hazards. So even if a green run or blue run is more difficult somewhere else, it probably lacks certain features that would qualify it as a more advanced run.

Honorable Mention (The Triple Black):

Now, I mentioned this specific ski trail difficulty earlier on in this article when I was laying out each difficulty. This run, as stated above, is unofficial; that means it technically doesn't exist in an actual rating scenario. Howeverm I feel like it deserves to be explained, and I'll point to some examples of a triple black. As you've likely already deciphered, a triple black is the most difficult type of trail you can go on. That's if were only speaking about ski resorts, of course.

I also want to note that triple blacks are not commonly found at every resort. These are extremely rare trails to find and should only be attempted by expert skiers, as the consequences for a mistake on these types of trails are extremely costly. The three most notable trails that have been given this rating are trails such as Big Sky's big couloir, Jackson Hole's Corbet's couloir, and smugglers' notch's black hole. All of these runs are technically labeled as triple black trails due to their extreme nature. They should only be attempted by extremely skilled and expert skiers who feel comfortable on double black runs and are looking for a challenge.