Nayls North is just like Nayls South, only harder. The climbs and descents are steeper, the sustained climbs are longer and the sandy bits always seem to be in the wrong place.
You'll doubleback across the limerock road 2 more times (with an additional outlet in the early going) before reaching the final section of the trail. The terrain changes from well packed leaf covered dirt to clean packed sand, but with a lot of palmetto roots almost set up like whoops. Fight to keep momentum up through here and you start the tight bit of the trail with trees flanking you through tight corners and short ascents. You'll hear and see cars on 49th street as you make your way back to the trail entrance.