How to Unlock Norikura Skyline Route in Forza Horizon 6

Steps to Unlock the Route
To get the pass onto your map, you need to clear a few campaign prerequisites and physically drive to the location.

Advance the Horizon Campaign Before you head out, make sure you have played through the initial stages of the Forza Horizon 6 Campaign. You need to progress enough to unlock the "free roam" mode so you can freely travel across the map.
Complete Yuki's Story (Chapter 1) This is a crucial detail that many players miss. Make your way to the car mechanic shop and complete at least the first chapter of Yuki's Story. Finishing this chapter guarantees that the local AI opponents and regional events will trigger properly when you finally arrive at the mountain.
Locate the Mountain Region Open up your world map and look all the way to the northwest corner. You want to focus on the area located directly south of the ski resort.
Drive the Pass Grab your favorite ride and physically drive out to that northwest territory. You must put your tires directly onto the mountain pass roads. As soon as you enter the area and break the fog of war, the formal Norikura Skyline layout and the "Norikura Descent" street race will officially trigger and unlock on your world map.

Troubleshooting Missing Events
Are you already sporting a Gold festival wristband but still cannot find the race icon on your map? Do not panic—this is a common tracking quirk that is throwing a lot of players off.
The event icon will stay completely invisible if there is even a tiny bit of grayed-out "fog" left on that specific stretch of road. The game's map discovery can be incredibly precise here. To fix this, simply drive the entire winding touge path from the absolute bottom all the way to the top. Once you have cleared out every inch of the gray road outline, the system will register the full route discovery and permanently pop the events onto your map.
Once it is unlocked, you will have full access to one of the most rewarding downhill and uphill challenges the game has to offer. Go grab your favorite drift build or grip car, clear that map fog, and see you on the pass!