Updated July 2nd, 2023
If you are thinking about learning to ski you might have some questions. One of them might be how do you keep yourself from going down a really steep trail. A ski resort looks like a giant maze of trails going in every direction. Ski resorts in the United States and Canada have a standard system of ski trail ratings and markings. Let’s take a look at ski slope ratings so you will know what to expect on your first trip to the mountain.
What do ski slope ratings and colors mean?
The US and Canada use a system based on 3 colored symbols to indicate ski slope levels. The Green Circle, Blue Square, and Black Diamond. These represent easy runs, intermediate runs, and advanced runs.
This system was adopted by the NSAA (National Ski Areas Association) in 1968. We can thank Walt Disney for the system still used today. Disney had plans to open a ski resort in California in the 1960s. As part of their planning process, they did a lot of studies on trail ratings. The ski resort never came to be but the rating system they developed lives on today. You can read more about it here.
This system is also used in Australia and New Zealand if you are ever interested in doing some summer skiing down under.

You will see all the colors represented on a trail map. See the example from Whistler Blackcomb below. Note it also includes Orange zones which are terrain parks.

Green Circle – Beginner Slope or Easy Slope
Green slopes with the Green Circle Symbol are beginner or easy runs. They generally have a slope gradient between 3 and 15 degrees. They are always groomed. They are usually not that steep. Some skiers call them bunny slopes or nursery slopes. They can be wide or narrow but the trail map usually is drawn in a way to show you if it’s a wide open slope or not. If you are new to skiing this is where you will spend most of your time.
Many resorts will label their cat trails as green runs. These are narrow, not that steep runs that crisscross the resort so you can get to different areas. Some cat trails labeled as green are not beginner friendly. At Snowbird, there are cat trails that are narrow with a lot of blind turns. Experienced skiers will ski these very fast. It’s nerving to ski a really narrow trail with people rocketing past you around corners. Snowbird is a very steep mountain that isn’t meant for beginners. If you are an inexperienced skier, don’t try the resort that uses marketing “1 our of 5 stars, too difficult”.
Blue Square – Intermediate Slope
Blue runs with the blue square symbol are intermediate runs. These tend to have a slope angle between 15 to 22 degrees. A blue slope is usually groomed. Some ski resorts leave some blue runs ungroomed especially on powder days. Runs with the Blue trail rating can have the biggest variation from ski resort to ski resort.
These are the runs where you should be comfortable parallel turning to ski. You can snow plough intermediate runs but your knees will hate you at the end of the day and it won’t be real fun. As an intermediate skier who can parallel turn you can probably handle almost any groomed blue run in North America.
Black Diamond – Advanced Slope
Black slopes with the black diamond symbol are advanced runs. Black runs tend to have slopes greater than 22 degrees. These runs can be groomed or ungroomed. Ski resorts like to have some steep black groomed runs for the speed demons out there. Other black runs are left ungroomed all the time for moguls or glade skiing. You should not try black runs until you can proficiently parallel turn and stop.

Double black, triple black, and other variations
You will see some variations on the markings at some ski resorts. It is common for ski resorts to rate their most difficult trails as double or triple black diamond. What is the difference between a black diamond slope or a double black diamond? It is the ski resort telling you to stay away unless you are an expert skier and to use a bit of caution. It is a steep slope and may have other obstacles such as cliffs, dropoffs, trees or large rocks to avoid.
Can double and triple black diamond runs still be groomed? Yes. Blue Mountain, Ontario has many runs they rate as double black diamond. Most of them are groomed every morning. They are just a little steeper than their black diamond slopes.
At places like Jackson Hole, the black diamond slopes are average difficulty. Most skiers can handle them. They save double blacks for truly dangerous, advanced runs such as Corbet’s Couloir. No one would say a ski descent of Corbit’s is for anything but the most advanced skiers.
The triple black designation is another level up. Again it just means the most difficult slopes at a ski resort. Many ski resorts don’t use triple or double black for that matter. Mount Bohemia has a chunk of their hill labeled as triple black. It is a zone with a lot of cliffs. That is the only difference between their double and triple blacks.
Another variation you may see is a black diamond on blue square. It is a run that is a more advanced blue or easier black. There is also a green circle on blue square. This is a more advanced easy run or easier intermediate run. These aren’t common. The difficulty depends on the snow condition of that run. It is a blue run on a groomed packed powder day. It is a black run on an icy or fresh snow day. Very few ski resorts use these so you may never see them.
Orange – Terrain Parks
You will see orange zones on some trail maps. This has become the standard way of marking terrain parks. A slope in a terrain park will still have a regular rating. A terrain park can exist on a green, blue or black run. The orange mark serves the purpose of telling people where on the mountain the terrain parks are. It doesn’t tell you how steep the ski run it’s on is. You should still pay attention to what level slope it is on and check out the features before trying it.

A blue here isn’t a blue there. Trail ratings are relative to the resort
The ski slope rating system in the USA and Canada gives you a rough idea of how challenging a slope will be. There is one caveat to that. Ski slope ratings are relative to the mountain you are at. Ski resorts no matter how big or small and no matter how steep they are all have beginner, intermediate and expert trails. Every single one of them.
The easiest 25-30% of runs will be green. The middle 30-50% of runs will be intermediate. The upper 25%-40% will be black/double black/tripple black.
An expert trail at a small 180 foot vertical hill is different from one at 3500 foot vertical Vail Resort. The Saddle at Whistler Blackcomb is a blue run. It is extremely steep and long. It’s groomed so it’s a blue run. Mogul Mania at Mt Holly Michigan is a black run. It has about 50 feet of vertical drop and isn’t very steep. Sometimes they let moguls form on it. You could fall at the top of Mogul Mania and slide 100 feet and be at the bottom. Falling on The Saddle can be a terrifying experience on an icy day.
If you can ski an expert run at your local hill, it does not mean you can ski an expert run at every ski resort in the world. If you are skiing a mountain for the first time, start out on the blue runs and work your way up. Get a feel for how hard an expert run is before you go bombing down a double black.
Groomed vs Ungroomed (On-Piste vs Off-Piste)
Most ski resorts groom some amount of their runs every night. Sometimes they groom during the day or between day and night skiing. A slope rating doesn’t tell you whether a slope is groomed or not. Almost all green runs are groomed. On a powder day you might find some that are not. Almost all blue runs are groomed too. Some ski resorts will leave some blues ungroomed to make easier mogul runs. Black runs and up are a mixed bag. Ski resorts will groom some black runs and leave some ungroomed.
You will also hear the term “Off-Piste” or “On-Piste”. These terms come from Europe but you will hear them sometimes in the US and Canada. Piste is the French word for a groomed run. On-Piste refers to a groomed run. Off-Piste refers to an ungroomed run. Europeans will sometimes refer to the trail map as the “Piste Map”
European Ski Slope Rating System
Europeans use a 5 color system of circles. Instead of Green, Blue and Black, they use Green, Blue, Red, Black, and Orange circles. A green run is beginner. Blue is easy. Red slopes are intermediate. Black is advanced. Orange is expert only. Some ski resorts use Yellow instead of black.
Some resorts will use Black for groomed advanced runs and yellow for ungroomed. Yellow may also indicate the run is not patrolled as well. You may be able to ski it but don’t expect the ski patrol to rescue you if you get in trouble. The meaning of black and yellow varies from country to country and resort to resort. It is good to do some research on the resort you are going to before heading down these runs.

Japanese Ski Slope Rating System
Japan uses 3 ski slope colors that is somewhat similar to the US system. They use green, red, and black circles. Green is an easy run. A red run is intermediate. Black is an advanced run. It varies from ski area to ski area with runs being relative to other runs at that place.

Wrap Up
Now you should be ready to head to the mountain and know what you are getting into. It’s always a good idea to do a little research into any mountain you are heading to before you buy a lift ticket and head up the ski lift. Some mountains are known for being not that steep and very beginner friendly. Other mountains are known for being steep. As long as you use some common sense and caution you can ski almost anywhere.
You might also like:
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- How to Stop on Skis – The 4 Best Ways to Stop and Helpful Tips
- 15 Great Snow Gods And Goddesses You Can Worship For Snow

Doug Ryan
Co-Founder & Chief Editor
I grew up back east in Pennsylvania and learned to ski on a family trip to Killington, Vermont when I was 6. I immediately fell in love with the mountains and outdoors and have been skiing across the US and Canada ever since. I went to school for Mechanical Engineering, and have a Master’s Degree in Material Science and Reliability.
I am a total gear nerd and love learning how things work and thinking about how they could be improved. Nothing excites me more than trying out new gear. I’d rather spend 3 hours taking my bike apart and learning how to change something than go to a bike shop. These days I reside in Michigan by the Great Lakes and go skiing, biking, and boating as much as possible.
doug@adventuregearinsider.com