In reply to johncoxmysteriously: Well this is misleading as its ultra-distance, so 75km, so Trail running world champs misses out the crucial bit.
But fell running is normally trackless.. mountain running merges with trail running much more. I suppose a ven diagram would be best where you have some races which you could class as any of the 3...
But this is 5 very runnable 9 mile loops with 1500ft ascent per lap, fully flagged out, no navigation.