About 2500 people are expected to run, walk, swim or bike around Blue Lake during the XTERRA Rotorua Festival this weekend.
The annual festival marks its 10th anniversary on Saturday.
The popular event will include activities for children, runs and walks for different fitness types and a feature triathlon challenge highlighting top New Zealand and international athletes.
Rotorua's Grant Utteridge said he was returning to have a crack at the main event this year.
"It's awesome. I've done the XTERRA individually the last couple of years. It's a medium distance triathlon with a really nice run and a tough ride with some mean climbs."