Police in New Zealand have said an Irish hiker, who went missing in Kahurangi National Park for almost two days, was very lucky to be found.

Siobhan Flynn was separated from her group on the first day of their trip and was unconscious for some time following a fall.

She is believed to have slept for most of the next day.

When she resumed walking she found a hut where an American doctor was staying and received treatment for a head wound and hypothermia.

Tasman District Communications Manager Barbara Dunn said the park is vast and it would be unusual to meet other hikers.

"The chances of running into anyone would be relatively slim. She's been incredibly lucky. The luck of the Irish, I guess."