Organiser Glen Christiansen said when he first thought about staging the event he thought if he was lucky he might attract 50 entrants, not the 198 who took part in the race at Goldfields Mining Centre near Cromwell on Saturday.
Mr Christiansen said he had never run an event like it before.
"But you've got to have a crack, don't you?"
The race involved either teams or solo runners and walkers running a marathon on a track around the centre. Participants completed eight laps of a 5.25km circuit.
The race was won by Clyde's Chris Keogh, who covered the distance in 3hr 51min 30sec.
Mr Keogh said he was surprised to win as it was his first marathon. He only took part in the event as preparation for next year's Challenge Wanaka triathlon.
After the race he said while it was not exhausting in terms of breathing, it was certainly tough on his legs.
Mr Christiansen said although there were one or two small things he might change for next year's event, he was "stoked" with how the first one went.
"Everybody seemed really happy. All the feedback I've had so far has been positive. It was just good fun."
He said one of the features of the race was it catered for everyone from serious runners to families who wanted to take part as a team.
"That was why we had people lapping back every 5km or so. People could cheer them on and have a good time."
He was also pleased heavy rain on the course early on Saturday morning was replaced by bright sunshine by the time the race started.
