This is Tyler's time for the Strava segment, which doesn't quite close the loop.
"It's been a couple years since I went for an all-out effort on the North Nasty! It was a perfect morning and I felt really happy about the effort I put out. The first 6 or so miles (until you get to the road section on Skyline) is where it really hurts, but then you get cruising Wildwood and descents and it allows for some recovery from the climbs to finish strong."
For the North Nasty route, there are gates at the start of the first descent and end of the last climb. This is what I've used for the route. The original instructions say to cross over from the Leif Erickson TH, but that's unsafe due to a blind corner and fast cars going by. If possible, I'd like to suggest that the route starts at the Firelane 9 gate and at the Firelane 10 gate, which is what the Strava segment uses.