A proposal to merge the region's four councils into one could have the surprising consequence of making Northland more than 50km longer.

The expansion of Northland's territory would come about because the proposed Northland Council would take in the Three Kings Islands, a cluster of 13 rugged islands 55km northwest of Cape Reinga.

According to the draft proposal for reorganising Northland's local government, released by the Local Government Commission on Tuesday, a single Northland District would include the Three Kings.

Although relatively close to the mainland, the islands are not currently part of any territorial authority.


They are classified as outlying islands and administered directly by the Minister of Local Government while the Department of Conservation is responsible for enforcing the Building Act on the rocky outcrops.

That, and other responsibilities, would pass to the new Northland Council.

The Three Kings cover less than 5sq km and are located on a submarine plateau separated from the mainland by an 8km-wide trough up to 300m deep.

Known as Manawa-tawhi or Nga Motu Karaka in Maori, they were named Drie Koningen Eyland (Three Kings Island) by Dutch explorer Abel Tasman in 1643 because he first saw them on January 6, the day the Three Wise Men are said to have visited the infant Jesus.

They were home to Maori at the time but have been uninhabited since at least 1840.

In 1945 the world's rarest tree was discovered there.

At the time, the kaikomako (Pennantia baylisiana) growing on one of the islands was the only one of its species on the planet.

The Local Government Commission is proposing to merge the Whangarei, Far North and Kaipara district councils with the Northland Regional Council to form a single Northland Council in 2015.