Green vs. Blue vs. Black: Understanding Levels of Ski Resort Terrain
Are you newer to skiing, or just want to understand the different types of terrain you might encounter at a ski resort? You may have noticed that every North American mountain uses the same general trail rating system, and while every hill is different, they all use similar rules of thumb when leveling their runs. What makes a “green” trail “green,” and a “blue” run “blue”?
In this article, we’ll unpack the various skiable terrain ratings -- including the green circle, blue square, black diamond, and double-black diamond -- to help you understand what to expect as you explore beginner, intermediate, advanced, and expert terrain on your ski day.
How did ski resorts arrive at the green circle, blue square, and black diamond rating system?
Before we get into the ratings themselves, it’s helpful to quickly start with how these colors and shapes came to be in the first place. And it turns out the origins of this system are actually fairly recent compared to the sport of skiing itself.
In the early 1960s, a group of ski industry professionals, including trail designers and ski instructors, gathered as part of the National Ski Areas Association, or NSAA. They recognized the need for a consistent and universal rating system that could help visitors determine the difficulty of different slopes.
By 1968, after years of discussion and collaboration, the group ended up going with a rating system that had been actually been pioneered by none other than the Walt Disney Corporation. Disney had designed the ratings for a planned ski resort that never came to fruition, but they put a ton of market research into analyzing which shapes would be instinctively associated with certain difficulty levels. The three-tiered system developed from this research was the green circle, blue square, and black diamond scheme we know today. This rating system was quickly adopted by ski resorts across the United States, finally allowing guests to reasonably estimate trail difficulties no matter the resort, and in the years since, has become a widely recognized standard worldwide.
Green Circle: Beginner Terrain
For most skiers, beginner terrain (often denoted on trail maps with a green circle) will be the natural first area on the mountain where they’ll spend time. Beginner terrain consists largely of two types of terrain: learning areas and beginner slopes.
Beginner learning areas (also known as “bunny slopes”)
Almost every ski resort will offer a dedicated beginner learning area, sometimes informally called a “bunny slope” or “bunny hill,” where skiers who are very new to the sport can develop initial fluency in a low-pressure terrain environment. Bunny slopes are groomed, gently-sloped, and generally spacious; they tend to be located near the base of the mountain (for easy access); and they often form a distinct, isolated “pod” of terrain (sometimes with its own, dedicated lift), separated from terrain for other levels of difficulty.
Beginner slopes
Once you graduate from the bunny slopes, you’ll want to branch out into other terrain labeled with a green circle on a trail map. Beginner slopes are more varied than beginner learning areas, but they are still generally quite consistently gently-sloped and groomed. While you won’t find moguls or steep sections on beginner slopes, you might find sections that are relatively narrow or (in rare cases) lightly-gladed, with well-spaced trees (e.g., at Beaver Creek’s McCoy Park).
Although most resorts will include some quantity of beginner slopes, there is significant variation in just how much. Some resorts, such as Beaver Creek, Deer Valley, or Okemo, offer abundant beginner terrain, including some beginner terrain off the peak of the resort (which allows beginners to access the top of the mountain and ski down safely) or beginner terrain with novel features (e.g., glades). Other resorts may offer only a beginner learning area or a few unremarkable beginner slopes near the mountain base, which can feel monotonous quickly. If you plan to frequent beginner terrain, we’d suggest consulting the trail map of any resort you’re considering visiting to confirm the quantity of beginner terrain on offer. Fortunately, at most resorts, beginner terrain tends to open early in the ski season and stays open consistently throughout the core season.
Blue Square: Intermediate Terrain
For skiers at the intermediate level of proficiency, intermediate-level terrain (often denoted with a blue square, or sometimes a double-blue square, on trail maps) offers a new world of diverse terrain to explore. Intermediate terrain is far more diverse than beginner terrain, and it can include relatively steep sections (where wedged turns will no longer be sufficient to control speed), moguls (on ungroomed runs, and only some resorts offer ungroomed blue runs), glades, or even high-alpine bowls.
Intermediate terrain is generally higher-stakes than beginner terrain -- if you’re unprepared, you can pick up more speed, and potentially collide with more dangerous obstacles (e.g., trees or moguls) than you would on a beginner run -- but, for skiers who have mastered beginner terrain, blue slopes offer a host of exciting, new aspects that will make for a more interesting ski day.
Still, skiers should not expect precipitously steep terrain, exposed rocks, cliffs, or similar obstacles on intermediate terrain, making blue terrain a relatively safe next step up for a skier who feels comfortable on green terrain and is ready to try a new challenge. Note that, at a small number of mountains, intermediate terrain may be split into two sub-levels -- blue, and double-blue -- with double-blue terrain typically indicating a level of challenge between intermediate (blue) and advanced (single black diamond).
Generally, intermediate terrain tends to be distributed fairly consistently across a mountain, and most mountains allow intermediate-level skiers to ski comfortably from peak to base. Like beginner terrain, intermediate terrain tends to be open early and consistently throughout the ski season. Fortunately, intermediate terrain is generally more widespread than beginner terrain, at most resorts, meaning that skiers who graduate to blue terrain will enjoy a significantly wider selection of skiable terrain at most mountains.
Black Diamond: Advanced Terrain
After feeling comfortable on intermediate terrain, skiers may want to explore the next level of terrain: advanced runs (which are typically denoted with a single black diamond on trail maps). Just as intermediate terrain represents a step-change in terrain diversity compared to beginner terrain, advanced terrain takes things up another notch, introducing a wide variety of novel characteristics that skiers can experience on trail.
Advanced terrain typically includes steep sections (where good technical turning skills are required to control speed), and it may contain wide-open bowl sections (with rocks or other obstacles) or glades (varying between widely-spaced glades, which are easier to navigate, and tightly-spaced glades, which are more challenging to navigate). Most advanced terrain is ungroomed (making moguls a possibility), although many resorts in the Western US maintain at least one groomed advanced-level run (and typical resorts in the Eastern US regularly groom several advanced runs). Also, ungroomed advanced terrain can be less crowded and more scenic than beginner and intermediate terrain, providing a sense of solitude and natural beauty that can’t be found on easier terrain.
Just as advanced terrain can feel much more exciting than intermediate terrain, it is also riskier and requires more care. Skiers attempting advanced terrain for the first time may want to do so cautiously, either by skiing with a more experienced partner, taking a lesson, or seeking out the least-challenging advanced level run possible, on a day when conditions are favorable. Under a worst-case scenario, advanced-level runs can introduce significant injury risk; for example, tree collisions on gladed runs, or high-speed collisions and slides on groomed runs (where it can be easy to gain excessive speed and lose control).
Adding risk, a small number of resorts have treated single-black as their most challenging trail map designation (for example, historically, Palisades Tahoe, which recently changed this practice -- see our coverage on that here), which means that highly-technical expert-level terrain may appear identical on the trail map to far less challenging advanced level runs -- if in doubt, ask a resort representative if this is the case at the resort you will be visiting.
Generally, advanced-level terrain takes slightly longer to open than beginner and intermediate terrain -- most resorts will keep most of their advanced terrain open during the core season, but such terrain may take a few more weeks to open in the early season compared to easier runs.
Jupiter Peak is a particularly technical double-black diamond area at Park City, Utah that requires hiking to reach.
Double-Black Diamond: Expert and Extreme Terrain
At the top of the scale, expert terrain (typically denoted with a double-black diamond on trail maps) represents the ultimate challenge. If you’re confident in navigating advanced terrain, expert-level runs may be the natural next step, and they can introduce both increased excitement and increased risk.
Expert terrain varies widely in level of challenge -- across different resorts, some may use the double-black label more generously than others, and even within the same resort, some double-black runs may be significantly more challenging than others. Still, in most cases, expert terrain includes at least one (if not several) characteristics that make for a challenging, highly-technical experience: for example, very steep pitches, exposed obstacles (e.g., tightly-spaced glades, boulders), very narrow and steep sections (e.g., chutes), sections requiring dropping in from cornices or cliffs, or sections otherwise requiring that skiers take a straight line down the fall line (“mandatory straightlining,” which can result in rapid, uncontrolled acceleration) or take jumps (“mandatory air,” which requires technical expertise and can likewise result in rapid acceleration). With few exceptions, expert terrain is ungroomed.
At some resorts, you may notice trail ratings that go even beyond double-black, such as “triple-black” (e.g., at Big Sky Resort) or “extreme terrain” (used by many resorts, especially in the Western US). In most cases, these ratings truly denote terrain that is more challenging (and more dangerous) than typical expert terrain, and skiers should heed extreme caution when approaching this terrain. To generalize, “triple-black” or “extreme terrain” tends to include more (or more extreme versions) of the typical defining characteristics (listed above) of expert terrain, with even less margin for error (and higher consequences in the event of error). Many runs with this designation develop reputations (sometimes even national) of notoriety among skiers (e.g., Rambo at Crested Butte Mountain Resort, which we skied here).
The Rambo trail at Crested Butte, Colorado is the steepest tree-cut trail in North America. Crested Butte rates this trail as an “extreme terrain” double-black diamond run.
Expert terrain, and particularly “extreme” or “triple-black” terrain, is inherently dangerous and should be treated with great caution. Expert terrain has a higher risk of falls (and of injury, or even death, from such falls), and it can introduce elements that even seasoned skiers may not have faced before (e.g., cornices, couloirs). In the event of injury, rescue (by ski patrol) from expert terrain can be slow and challenging. To drive home this message, many resorts display prominently at the entrance to expert-level runs warning signs (often, handwritten by resort staff) with earnest pleas for caution. For these reasons, we recommend approaching expert terrain with a great deal of caution, skiing it with a partner, and skiing it defensively.
With that said, once you feel comfortable on expert terrain, you can enjoy what is often the most dramatic, isolated, and awe-inspiring terrain at most resorts. Crowds on expert runs (and any lifts specific to expert terrain) are generally sparser than less challenging terrain, and snow tends to stay fresher for longer. At many resorts, expert runs offer a level of solitude, a distinctive aesthetic, or sweeping views that other terrain types cannot offer, and that alone is reason enough for many skiers to want to try them. Many skiers specifically seek our resorts with the best challenging terrain -- to reflect that, PeakRankings rates each resort we rank on the Challenge category, which rates the experience a resort delivers for expert-level guests (for more detail about the Challenge score, one of ten categories that make up the PeakRankings Mountain Score, click here).
Logistically, expert terrain tends to be the last section of terrain to open for the season at most resorts, and it may be more likely to close (even during the core season) for inclement conditions, owing to its steep pitches and (often) greater isolation and exposure to wind; if you plan to ski expert terrain, aim to visit resorts during the core season, once such terrain has had a chance to fill in with the requisite natural snowfall (seldom do expert runs receive snowmaking). At most mountains, expert terrain is located at upper-mountain areas, which tend to be steepest, but this generalization doesn’t always hold. Lastly, more often than for other types of terrain, expert terrain may be serviced by slower lifts or surface lifts (due to low skier demand), or it may not be lift-serviced, at all (requiring a hike or ride in a vehicle to reach). Still, for some skiers, the effort (and risk) inherent to expert terrain is outmatched by the distinctive characteristics of this terrain type.
Orange Oval: Freestyle Terrain
And finally, we would be remiss if we didn’t mention the distinct designation for freestyle terrain, often represented by an orange oval on trail maps. Orange freestyle designations are often assigned in addition to a trail’s difficulty-level trail rating, such as green, blue, or black, rather than in lieu of it -- but they signify that a trail includes one or more terrain park features, such as boxes, rails, jumps, jibs, or pipes. At some resorts, typically larger destinations, orange ovals can encompass natural features such as natural jumps, rock formations, and tree stashes, providing a unique blend of creativity and the surrounding environment.
Orange ovals can signify features ranging from the smallest progression parks to the most extreme pro-level jumps, but they’re often embossed with a size designation, ranging from XS to XL, that designates how technical the obstacles are. But regardless of the level, navigating these orange-designated features requires a combination of balance, control, and creativity that most non-freestyle ski resort trails don’t require.
Final Remarks
Whether you are a beginner-level or expert skier, we hope this overview helped to demystify the various trail ratings and terrain types that collectively make up a ski resort. As a caveat, note that trail ratings are subjective, relative, and vary from one resort to another -- runs labeled as “green” or “blue” at one resort may be easier, or more challenging, than “green” or “blue” runs at other resorts -- there does not exist a standardized, uniform rubric that all resorts use to rate their terrain objectively.
Have any thoughts, questions, or reactions? We’d love to hear from you, so be sure to hit us with a comment below!