The weekend event sees teams of four walk 50 kilometres in 18 hours or 100 kilometres in 36 hours to raise money for Oxfam's work fighting poverty.
A total of 168 teams set off this morning. Most of them will continue walking all night, finishing by 6pm tomorrow.
Oxfam New Zealand's Executive Director, Rachael Le Mesurier was impressed with the achievements so far.
"It's always a real thrill to watch the first team cross the line and the atmosphere from locals and volunteers cheering them on was buzzing.
"The warm welcome received from Whakatāne has been brilliant so far, as always, and will play a huge part in buoying the spirits of tired walkers.
The first team to cross the 50km line was Auckland team Taking It Easy, in 10 hours 31 minutes.
Once the teams have rested they will continue to fundraise until the cut-off in April.
Oxfam Trailwalker has so far raised almost half a million dollars to support Oxfam's humanitarian and long-term development work in some of the world's poorest countries.