Orienteering Bay of Plenty secretary Darren Ashmore said there were about 500 competitors registered for the Great Forest Rogaine.
"There are also the secondary school competitors, the juniors will do the three hour and the seniors the six hour, and they're coming from all over the North and South Island.
"It covers quite a big area, this year's six-hour event this year will have checkpoints spread out right across the Whakarewarewa Forest, all the way out to Green Lake from where it starts near Whakarewarewa School.
"The idea is that there are too many checkpoints for any team to gather within the time limit, so you have to be quite careful and strategic in your planning. They've got a good hour before the event to sit down with the map and do their planning. It's really important their planning includes getting back on time, because they lose points for every minute they're late."
He said the Whakarewarewa Forest was ideal for this sort of event.
"It's pretty awesome, there's such an amazing network there. The event this weekend includes the option of doing it on foot or on a bike - there's a unique map for each.
"Typically rogaines are done on foot, but mountain bike orienteering and mountain bike rogaining are growing in popularity, we've always had it as part of the Great Forest Rogaine," Ashmore said.
Teams would be able to compete at their own pace, meaning the event catered to all skill and fitness levels.
"There will certainly be lots of fairly novice teams, that are just coming along for the fun to see how far they can get and where they can get to.
"Rogaines right around New Zealand are gaining popularity. It's good fun and it gets you out into a nice bit of nature, doing physical activity and the added element of having to use your brain and work with your teammates through the problem solving and strategic side of it. That certainly appeals to a certain type of person and there's plenty of them out there."
Registrations closed on Wednesday night, but there will be a limited number of entries available on the day, on a first in, first served basis. For more information go to www.obop.org.nz