"We fluked it really. We did not expect to win. She wanted to do it. I only entered because she did," jokes Ben.
"We did not know until the end that we were first. We are stoked."
Alyssa's father Brent (49) and brother Richard (25) won the male team event.
It was also the first event around the mountain for Brent, but Richard had placed third in his age group and ninth overall in a previous cycle event around Mount Taranaki.
Finishing the race in four hours and 10 minutes, they say they were elated with the result as they just entered for the ride.
"We just went to have a go and have fun," says Brent.
Richard adds they were in a good position from the start.
"We were in the front positions already at the halfway point."
Brent and Richard both joined the Stratford Cycling Club this month, with Alyssa and Ben saying they will most likely also join.
"I think I have caught the bug," says Alyssa. "I only got my bike in November."
The four each won a smart phone and say they will enter again next year, though they might have a go at the solo races.
The Stiellers will compete in the half ironman held in New Plymouth on February 9. Richard is entering solo, but Brent will compete against his other son, Reece (23), who will enter as part of a different team.
