Japanese man Reiitsu​ Anamizu​ is worried about nuclear war.

So worried that he bought a house in suburban Christchurch and built a concrete nuclear bunker, complete with thick lockable doors, a water cleaning system and an escape shaft, in the backyard.

He figured New Zealand would be a safe haven in World War III because there are fewer nuclear weapons in the southern hemisphere.

CHRISTCHURCH CITY COUNCIL The 44-square-metre concrete bunker has thick metal and concrete blast doors. These 2005 photos are from the Christchurch City Council's planning file for the bunker.

Anamizu lives in Japan and has a second bunker under his home in the northern city of Aomori​. He completed his first shelter in the backyard of his Avonhead house in 2006.

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Speaking from his Aomori health clinic, he told Stuff through a translator that he was worried about the Middle East and Syria. He was concerned Syria "would come up fast" if World War III broke out. He said he was worried that nuclear problems were getting worse in the world.

ANAMIZUREIITSU.COM Japanese man Reiitsu Anamizu lives in the north of Japan, but owns a nuclear bunker in Christchurch.

He chose to build his nuclear bunker in Christchurch because it has a similar climate to his home town.

He wants to live in Christchurch in the future, he said. He has visited a few times in the past, but not for the last few years. In the event of a nuclear emergency, he said he may need both his Christchurch and Japanese bunkers, depending on the circumstances.

In recent years, there have been many reports of American billionaires buying South Island properties as bolt holes from what they believe is a coming apocalypse. The 'doomsday preppers', as they are known, have also reportedly built secret nuclear bunkers on their South Island properties, although there is little evidence to prove the claims.

CHRISTCHURCH CITY COUNCIL The only sign of the bunker in the backyard is the top of a concrete shaft that runs down to the shelter.

But Anamizu was ahead of the trend, building his Christchurch bunker about 12 years ago.

The tenant in Anamizu's Avonhead home declined a request to view the bunker, but photographs from the Christchurch City Council's planning files show how the shelter looked in 2005.

A casual observer standing in the backyard would have no idea they were standing above a 44-square-metre concrete underground bunker. The only visible sign of the bunker is a concrete cube on the lawn with a metal grille door in the front.



Beyond the metal grille door is a concrete shaft, with metal rungs running along one side, that leads down to the bunker itself.

CHRISTCHURCH CITY COUNCIL The bunker is reached by about a dozen steps behind a door in the garage.

The shaft probably acts as an escape hatch if the main entrance is blocked.

The main entrance to the bunker is down a flight of about a dozen concrete steps behind a door in the back of the detached garage. The bunker features thick metal-framed, concrete doors with large metal vault locks. Media reports in 2006 said the doors were armoured and blast-proof. The reports also said the bunker featured battery-operated lights, a hand-pumped water purifier and a ventilation shaft.

The tenant in the house, who finished the conversation with Stuff before giving his name, said he had no desire to use the bunker.

CHRISTCHURCH CITY COUNCIL Images of what appears to be a hand-pumped water purifier system in the bunker.

"If nuclear fallout comes along I certainly wouldn't want to be in it," he said.

"I don't know much about nuclear bombs, but I've been led to believe that everything out here is effed for a very long time. The water is contaminated, the earth is contaminated.

"Why would you want to spend the rest of your days in that thing? Once the food runs out, what is going to happen?"

CHRISTCHURCH CITY COUNCIL A thick metal and concrete blast door seals off the bottom of a shaft leading from the backyard. The shaft appears to have metal rungs running up one side.

He said the bunker was an empty shell with no store of food or water.

"I don't have any reason to go in there. It's just a concrete hole. There is nothing special about it."

But he said Anamizu was an "awesome landlord".

The bunker may be unique in Christchurch. Council head of building consenting Robert Wright said a search of their entire planning database found only the Avonhead bunker, which was approved in 2006, and an application for an "underground storage shed', which was approved in 1999.