The fourth annual Northburn 100 Mile (160km), 100km and 50km races will begin this morning on courses over steep terrain on Northburn Station, near Cromwell.
''The weather forecast is looking awesome ... which is actually a bit of a worry because we have a reputation for extreme weather - we've had snowstorms and 100kmh winds in the past - so some people may be disappointed if the weather is too `nice','' race director Terry Davis said.
''Northburn is not about being nice or having fun.''
The number of entrants has increased again this year and athletes from Europe, the United States, Jakarta, Hong Kong, Japan and Australia will line up alongside New Zealand endurance runners. Forty-nine have registered for the 160km, 22 for the 100km and 48 for the 50km.
''We have some big names this year. Sage Canaday, from Colorado, is one of the best in the world. It's a bit of a coup to have him here, really,'' Mr Davis said.
Canaday has entered the 50km event and is fresh from a win at the Tarawera ultramarathon last weekend. Although the Northburn 160km is the main attraction, the 50km race was gaining a strong following as well.
''It's good to see a few locals getting in on that too,'' he said.
''The first 50k loop which we use for the 50k race is the nicest part of the whole course. There is a great variety of terrain, from 4WD tracks to sheep tracks, to small alpine streams to no track at all - you just have to follow the markers across the tundra-like landscape.
''I guess some folks are put off by the whole 'hard-core' reputation the event has but the reality is the 50k really isn't too bad because the ups are so steep you can only walk them, slowly, anyway. We have seriously had a very wide range of ability complete the 50k, the quickest in under 5 hours and the slowest in just over 13.''
Last year's 100km race winner, Matty Abel, of Sydney, will defend his title.
Jean Beaumont, of Wellington, who was the first woman home in the Northburn 100 Mile race in 2012 and second overall, is a title contender again this year.
''It will be interesting to see how well she does this time and Glenn Sutton, who beat Jean to win in 2012, is back too, so he's also a good prospect for another win.''
Honolulu competitor Hannah Roberts is another hot prospect in the 100 mile distance. Mr Davis said the event catered for runners of all abilities. There was a mountain half-marathon event today and then a 5km or 10km run tonight.
An adventure race had been organised for children tomorrow. Volunteers were a pivotal part of the race, he said. The Cromwell running group had been marking out the course and many of them were volunteering again at the weekend.
''All the volunteers are awesome - they're doing eight to 12-hour shifts, right through the night for some of them.''
