Plaque marking centre of New Zealand’s territory installed near Greytown - 18/04/2019

A plaque marking the geographic centre of New Zealand‘s Extended Continental Shelf has been erected in the Tararua Ranges, 11km northwest of the Wairarapa town of Greytown.

The plaque is a collaboration involving conceptual artist Billy Apple®, GNS Science, and the Department of Conservation.

Since 2008, the United Nations has recognised that New Zealand’s territory includes our undersea continental shelf as well as the land mass above the sea.


It’s a small but important reminder that our continental land mass does not end at the coast line, but extends out beyond the horizon, with about 95% of New Zealand’s territory lying beneath the sea.

Dr Cornel de Ronde


New Zealand scientists made a successful submission to the UN for recognition of our Extended Continental Shelf in 2008. This resulted in an extra 1.6 million km² of seafloor being added to New Zealand’s exclusive economic zone.

The project was a joint effort by GNS Science, the National Institute of Water and Atmospheric Research (NIWA), Land Information New Zealand, and the Ministry of Foreign Affairs and Trade.

Intrigued by the notion of this large underwater realm, Billy Apple asked the question: ‘Where is the centre of New Zealand’s extended continental shelf area?’ During the 1970s this was a conceptual art question he posed to reveal the nature of exhibition spaces.

Auckland-based Apple approached GNS Science about creating an art work based on a large survey pin that would mark the geographic centre of this vast land and marine territory.

Cornel and Jenny

It covers approximately six million sq km – equivalent to 14 times the size of California, eight times the size of Texas, or 1 percent of the Earth’s surface. About 95% of this territory is underwater and it is remarkable that the centre of this area falls on the five percent that is above sea level. 

GNS Science researcher Jenny Black carried out the calculations that identified the centre as being on Department of Conservation land in the Tararua Ranges. DoC helped to install the stainless steel artwork beside the Mount Reeves Track, which runs close by the centre point.

Apple says his focus on art and life meant that his work dealt with real issues. “The collaboration with Cornel de Ronde and his team at GNS Science has been a great opportunity and keeps art relevant.”

DOC’s Wairarapa Operations Manager Kathy Houkamau says, “We’ve always considered Wairarapa and the Tararua Rangers to be the heart of the country. It’s nice to discover this has geographic truth.

“We hope this encourages more people to get out and explore Wairarapa’s natural spaces.”

GNS Science marine geologist Cornel de Ronde, who along with Apple has been a driving force behind the project, says that the plaque signifies a new way of understanding our place in the world.

“It’s a small but important reminder that our continental land mass does not end at the coast line, but extends out beyond the horizon, with about 95% of New Zealand’s territory lying beneath the sea.”

The underwater territory straddles the boundary between the Pacific and Australian Plates and includes submarine volcanoes and a subduction zone that is part of the Pacific Ring of Fire. Because of this, it is potentially the source of large earthquakes and tsunamis.

“We need to explore this underwater frontier so we can better understand the underlying geology of our country and enhance our ability to deal with the natural hazards,” de Ronde says.

The circular stainless steel art work, which is 1m in diameter, was installed with the aid of a helicopter.

The image on the plaque shows the outline of the main islands that make up New Zealand sitting inside the silhouette of New Zealand’s Extended Continental Shelf boundary. The exact coordinates of the geographic centre are inscribed around the plaque: 175° 21.737’E, 41° 1.093’S.


Continental Shelf