Green circle trails are the easiest trails of a mountain. They are usually wide, groomed and offer a friendly, slight slope. Green circle trails are popular with beginners and are occasionally referred to as bunny slopes.

These trails offer intermediate difficulty. They are steeper than beginner skiing trails but still easy enough for intermediate skiers to ski. Blue square trails are not extremely raised or steep. They are accepted, well-known trails at most resorts, because they provide skiing that is fun but not scary. Generally groomed, some blue square trails have easy moguls or very easy glades.

These are difficult trails that are for advanced skiers only. Black diamond trails can be cramped and steep. Other challenges, such as icy conditions, may cause a trail to be marked as a black diamond. Most glades and mogul trails are black diamonds.

Trails receive this rating if they have exceptionally steep slopes. These are extremely difficult trails that should only be tried by expert skiers. Because of hazards such as extremely steep slopes, difficult moguls, glades or drop offs, double black diamonds should be approached with caution and only be skied on if one is sure he or she is advanced and experienced enough to handle the challenge.

Variations such as doubling a symbol to designate increased difficulty or combining two different symbols to indicate an intermediate difficulty are occasionally used at some resorts.

While not used at all ski resorts, these trails are represented by an orange, horizontal oval-like shape. Most ski resorts also add an official rating, so you will know how challenging the terrain park is.