A group known as the Jandal Sisters has been frequenting Quarantine Island for the past five years.
Member Tina Forrester said the idea came after another member visited the island in Otago Harbour and said it was "lovely".
Now, the group of about 12 women dress to a theme (this year it is recycling), pack their chilly-bins, and head for a weekend on the island every March and November.
Pip Hughes said it was "like a mini-holiday over there".
"It's a chance to get away from hubby, kids, and the pressures of life."
While the women are on the island, the focus is on relaxing and having a laugh.
They eat, drink, play games, go swimming and each night is like a mass sleepover when they drag all the mattresses into the homestead lounge.
"It's a nice way for the girls to have a treat."
