"I'm just lost in the moment of it.
"The run takes place in an area of significant spiritual value to the people of Te Arawa and the organisers fully acknowledge that the ability to run the event in such a location as a privilege."
Co-owner Tim Day joined Charteris in ownership a few years after he first ran in the event and said he was excited to see where it would go.
"We always wanted it to go further," said Day, who said they were happy the new owners had the same vision for the event.
Ironman Oceania managing director Dave Beeche said they were honoured to take up the challenge to further grow and nurture the event on the values of Charteris and Day.
"Paul, Tim and the team have done a wonderful job over these past 10 years delivering an event of high quality on some amazing and inspiring trails through the Rotorua heartland."
Charteris and Day would both remain part of the event.
Beech said they looked forward to working with the men to take the Tarawera Ultra to an even larger and more globally diverse audience.
While the trail run itself catered to a range of capabilities, the event brought a sense of community to volunteers, medical staff and those there to support loved ones.
Born and raised in Rotorua, Ngongotahā doctor Ben McHale owned Ascent Medical Support on the side of being a general practitioner.
His team offered medical support at a range of sporting events and had helped with the ultra-marathon for the past five years.
He said the event had a "cool vibe" and it was a chance to meet all sorts of people and mix his love of sport with his job.
He hoped to continue to be part of the event in the future under the new ownership.
New Zealand's largest ultra-marathon broke it's participant record this year with 2400 signed up to take those first strides.
Clinton Parkes was one of them and he had just completed his first marathon and ultra marathon in one hit - the 50km in a time of 5 hours 58 minutes.
An ultramarathon is any long distance running further than the marathon distance of 42.195km.
The 45-year-old AirNZ engineer from Auckland had participated in the event relays in previous years and decided to do the marathon when the relay was not offered this year.
Parkes said the atmosphere of sense of community of the event is what kept drawing him back. Something him, his wife and their two sons looked forward to each year.
"It's just special."