With your ski tips hanging over the edge of an easy Green traversing road, are you ready to shoot down a steep, mogul-filled Black Diamond, or do you just want an intermediate Blue to get down?! Ski trail signs are named and rated with different colors and shapes based on their level of difficulty, which makes it easy for skiers to know what's coming. A personalized ski sign replica of your favorite trail sign would bring that run right into your office. A custom ski sign with a meaningful color and your friend's name or an inside joke makes a great, unexpected gift that will remind them of those ski trip memories for years to come.
Image by Signs of the Mountains.
North America uses about five combinations that all mean pretty much the same thing no matter which mountain you're on, while other ski mountains in Europe or Japan use slightly different symbols to mark their "pistes" (that's what Europeans call their trails). The difficulty ratings are primarily based on the grade or steepness of the trail, and also take into account other factors like width and wind protection, and whether or not the trail is groomed. Each mountain rates its own trails, so the exact meanings are relative within each mountains’ system. Groomed trails have large tank-like trucks (snowcats) drive up and down the trails, pulling behind a "grooming drag" to pack the snow for easier skiing. Without grooming, moguls or bumps develop over time after many skiers turn back and forth and push the snow into mounds.
Image Source: http://en.wikipedia.org/wiki/File:BR180.JPG
Green Circle: The easiest; usually wide, open trails with a grade from 0-25%. (A 100% grade would be a 45-degree angle.)
Blue Square: Intermediate; generally the most prevalent rating across a mountain, with a grade between 25–40% and often groomed.
Black Diamond: Most difficult; steeper than 40%, likely ungroomed and therefore covered in moguls and/or the freshest snow.
Double Black Diamond: Experts only! Very steep and narrow, with extra hazards and obstacles like exposed rock and drop-off cliffs.
Orange Rectangle, horizontal with rounded edges: Terrain park; this is where you'll find rails and boxes, professionally shaped jumps and half-pipes.
A few ski mountains in North America combine these symbols, like a black diamond on top of a blue square to indicate a level in between the two. In Europe, they do not use different shapes, and in general, their Blue = North American Green, Red = Blue, Black = Black. The German Skiing Association DSV has implemented a few standards, though symbols and colors can still vary from country to country, and there are also a few other colors like orange and yellow worked in for more extreme trails. For a custom sign based on the Alps, you may want to double-check which side of the border you're on and their exact symbology.
For a vintage ski sign, use the original colors that the USA started using in 1964 until 1968:
Green Square for “easiest”, Yellow Triangle "more difficult,” Blue Circle "most difficult,” Red Diamond "extreme caution.”
If you're still a bit baffled on which ski sign-color/level to choose, keep in mind that a double black diamond could be for either a really good skier, or for a beginner skier as a goal, or a joke. And the opposite could be used as well. For example, a green circle could be used for a beginner skier or as a joke for a good skier. A Euro-style or Japanese coded sign could make a great ski gift for a foreign adventurer, or a vintage sign could be a fun throwback. An Orange sign could be just right for an extreme trickster, on skis or as a snowboard sign.
Here’s a quick, fun overview of the signs from the US National Ski Patrol.