Rotoroa Island off the coast of Auckland is to open to the public for the first time in more than 100 years.
The 82-hectare Hauraki Gulf island, owned by the Salvation Army, had been closed for use as a drying out facility for alcoholics.
Wealthy business couple Neal and Annette Plowman have bought a 99-year lease and formed a trust which will provide access to the island as a gift to the people of New Zealand.
The trust website shows it is also selling off 10 lifestyle blocks on the island.
Salvation Army secretary for business administration, Bruce Vyle, says the organisation is pleased the island will be used as a conservation park because that fits with the church's beliefs around preserving the Earth.
Work is underway to build trails for nature walks and to regenerate native bush. People will be able to visit the park from the end of February 2011.