The hardest ski run in the 3 Valleys (Les Trois Vallées) is widely considered to be the "Grand Couloir" in Courchevel. Here are some details about this challenging run: Location: The Grand Couloir is located in Courchevel, one of the resorts in the 3 Valleys area. Access: It can be accessed via the Saulire cable car. After disembarking, there is a traverse along a narrow ridge to reach the start of the couloir. Difficulty: The Grand Couloir is known for its steep gradient and narrow, sometimes icy, entrance, making it a true expert run. It has a steep pitch, often with moguls and variable snow conditions. Terrain: The run is off-piste but is considered a marked itinerary. It is steep, with sections exceeding 33 degrees in angle, and requires confident skiing ability in variable conditions. For those looking for a challenge and who possess advanced skiing skills, the Grand Couloir is a must-try in the 3 Valleys.