The Tarawera Ultramarathon may be in its 11th year, but it continues to grow.
The iconic event, being held this weekend, routinely attracts hundreds of runners and walkers from all over the world and this year is no different.
With later entries still to be counted, there are 2100 people signed up this year, a massive increase on the 1450 who took part last year.
"The main reason is our 50km event this year has proven extremely popular," said organiser Paul Charteris. "It's a nice little sweet spot for people who have done a marathon before, or even a half marathon, and they're deciding they want to do an ultra. The 50km is a good place to start."
There is also a new distance this year, the 20km, which had attracted about 600 participants. Entries for the 100-mile (160km) and 102km races are similar to last year.
The event caters for those looking to challenge themselves and try something new, but at the other end of the scale, it also attracts elite runners from all over the world and this year's line-up is as impressive as ever.
In the 102km race, Charteris said the woman to beat would be Courtney Dauwalter, of USA, who was named Ultra Runner of the Year in 2018. Her achievements include winning the Moab 240 Mile Endurance Run in 2017 as well as Western States 100 and Ultra Trail Mt Fuji 100 last year. She is taking on the Tarawera Ultra for the firs time.
Among those taking her on will be Italian-born Kiwi Cecilia Flori and USA's Sally McRae who won the 100-mile race here last year but has switched to the 102km for the 2019 edition. Australia's Jess Carroll, USA's Kat Schuller and New Zealand's Fiona Hayvice, who won the 102km race in 2016, will all be in the mix as well.
"That's a big international field, but Courtney is definitely a superstar of the sport," Charteris said.
In the men's 102km race, USA's Cody Reed will be looking to go one better than last year when he finished in second place. South Africa's Ryan Sandes has ticked off wins in the 4 Deserts, Leadville 100-miler, TransGranCanaria and Western States 100-miler races and is looking to add Tarawera to the list.
British runner Harry Jones, Australia's Ash Watson and USA's Charlie Ware will also be pushing to be in the lead pack.
"They are genuinely all contenders, it's a crazy strong field."
The standout in the 100-mile race is Camille Herron, of USA.
"Camille broke the 100-mile world record late last year, so she will be in phenomenal form for this one. Challenging her will be Jeff Browning, from USA, who won the Hardrock 100-miler last year - the hardest 100-miler in the world."
Last month Ironman announced the acquisition of the Tarawera Ultra-Marathon. Both Charteris race director Tim Day will stay on with the event, continuing to deliver a world-class experience with the guidance and support of the Ironman team.
Ironman regional director New Zealand Chris Randle said he had thoroughly enjoyed watching the Tarawera Ultra team go to work behind the scenes, setting up for this weekend's event.
"We're absolutely fizzing. I didn't meet Paul and Tim until recently, but they didn't know that we have been quietly admiring what they do from afar for quite some time. The way this event has grown with such a high calibre of international runners - the elite field is out of this world - and just the way that it is loved.
"It's pretty rare for an event to be loved like this one is and I think that's testament to the work they do. There's two sides because we're excited to be working with this team - everyone involved. It's the people that make these things so successful.
"It's also the community of trail runners which is incredibly special. Trail running has got a spirit to it which a lot of other sports don't have. There's almost this deep, spiritual bond between trail runners," Randle said.
The 20km race is being held today, which gives participants the opportunity to watch people finish the longer distances during the weekend.
The 100-miler starts at 4am on Saturday, the 102km at 6am and the 50km in waves from 7am. All runners finish at the Energy Events Centre in Rotorua.