When this trail was new, it got its name because it had a very smooth surface. After a few years of impact from use and the forces of nature, it has become less dirty. But it's still a cool trail with some long nice stretches with the possibility of good speed.
The path starts at Utsikten (Google Maps link: https://goo.gl/maps/2HEcxQpBE7zX6pFy9)
The cycling stage from Nesbyen to Utsikten is described here: https://trailguide.net/2210