Svalbard Global Seed Vault: How the Doomsday Vault Works

The Svalbard Global Seed Vault is Norway’s backup store for the world’s crop seeds, cut into a mountain near Longyearbyen and kept at −18 °C. Gene banks send copies of their seeds there, keep ownership of every box, and can take them back if their own collections are lost.

Svalbard Global Seed Vault at a glance

The official description is short. The vault was carved into solid rock and opened on 26 February 2008; its seed store lies more than 100 metres inside the mountain, under 40 to 60 metres of rock, where the permafrost sits at a steady −3 to −4 °C and an extra cooling system brings the halls down to −18 °C.¹ The Norwegian government set it up and paid for all of it, but the seeds belong to the gene banks that sent them.² The counter on the vault’s own website read 1,417,799 seed samples of 6,587 species when we checked in November 2026.³

Why build a seed vault at all?

Seed banks already existed long before 2008. What they lacked was a spare copy somewhere safe. The vault’s purpose, in its own words, is “safe, free and long-term storage of seed duplicates” from gene banks around the world, and its main value is as a back-up if the originals or the usual duplicates are lost.² Every sample in it is already held in a gene bank elsewhere, which makes Svalbard the second line of defence, not the first.⁴

What goes in is food and farming: crop varieties, farmers’ landraces, breeding material and the wild relatives of crops that could one day donate a useful gene. Wheat and rice each account for more than 150,000 samples and barley for close to 80,000. About two thirds of the samples come from the CGIAR international research centres, such as CIMMYT, IRRI and ICARDA, and the largest national depositors are the gene banks of the USA, Germany, Canada and the Netherlands.⁴

Cary Fowler, who helped create the vault, has spent years arguing against its nickname. He told The Washington Post in 2016 that it isn’t a doomsday vault or a time capsule: the seeds are alive and meant to be used.⁵ Fair enough, though “the crop backup drive” was never going to catch on in the headlines.

Why Svalbard?

The Crop Trust gives the short answer: the cold climate and the permafrost make the area “a perfect location for underground cold storage”, and the rock keeps the rooms frozen even if the machines stop.⁶ NordGen’s Åsmund Asdal adds two less obvious reasons: Longyearbyen has good infrastructure and public services, and there’s international confidence in Norwegian management.⁷ An airport about a kilometre down the hill doesn’t hurt either.⁸

It also wasn’t the first seed store on the island. In 1984 the Nordic Gene Bank, today’s NordGen, put backup copies of the Nordic seed collection in a steel container inside Coal Mine 3 outside Longyearbyen. The idea of a global store in Svalbard had been discussed since the 1980s, but a feasibility study in 2004 found that the permafrost in the mine was “not optimal” for high-security global storage. In October 2004 the Norwegian government committed to funding a purpose-built vault, and in 2005 it gave the planning to Statsbygg, its public building agency.⁹

Timeline

• 1984 The Nordic Gene Bank stores backup seeds in a steel container in Coal Mine 3, Longyearbyen.
• 2004 A feasibility study backs a new vault; Norway commits to building and funding it in October.
• 2006 The prime ministers of the five Nordic countries announce the vault on Svalbard in June.
• 2008 The vault opens on 26 February.
• 2015 ICARDA makes the first withdrawal, after the war in Syria cuts it off from its gene bank at Aleppo.
• 2016 Heavy rain in October sends more water into the entrance tunnel than ever before.
• 2019 A new watertight concrete entrance tunnel and a separate service building are finished.
• 2020 Holdings pass one million samples; the Cherokee Nation becomes the first Indigenous group from North America to deposit.
• 2026 Holdings pass 1.4 million samples; the vault receives the Princess of Asturias Award for International Cooperation.

The dates in the timeline come from the vault’s history page, the Crop Trust and Asdal’s 2025 paper.⁹⁶⁷ On opening day the Norwegian prime minister, Jens Stoltenberg, and the Nobel Peace Prize laureate Wangari Maathai placed the first seeds, and the first shipments filled 676 boxes weighing about 10 tonnes.¹⁰

Inside the vault: tunnel, doors and cold rooms

From the outside you see one thing: a narrow concrete portal sticking out of the slope, about 130 metres above sea level. Behind it a tunnel runs into the mountain and ends in a cross hall, with doors into three seed chambers. Each chamber is cooled to −18 °C, and 40 to 60 metres of solid rock sit above them.⁷

The press release for the opening described the way in as four locked doors: heavy steel entrance doors, a second door far down the tunnel and two keyed, air-locked doors at the end. The keys were coded by access level, so not every key opened every door, and motion detectors were placed around the site.¹⁰ That’s about as much as the operators have published, and it’s as much as we’ll repeat.

The measurements don’t agree

We expected the dimensions of a government building to be settled. They aren’t. The vault’s own site gives each hall a base of about 9.5 by 27 metres, while Asdal’s paper says 12 by 27.¹⁷ The tunnel is 80 metres in Asdal, about 100 metres in 2017 press coverage and 125 metres in the opening press release.⁷¹³¹⁰ Depth is “more than 100 metres” on seedvault.no, 120 metres (393.7 feet) on the Crop Trust’s site and about 130 metres for the whole construction in Asdal.¹⁶⁷ Some of that is simply measuring from different points, and the 2019 rebuild changed the entrance. In this article we use the official site’s figures.

What happens if the power fails?

The cooling runs on public power from the plant in Longyearbyen, with generators for outages.¹ If both failed, the halls would warm only towards the temperature of the rock around them. The Crop Trust puts it plainly: permafrost and thick rock “would keep the seed samples frozen even without power”.⁶ For a vault, that’s an unusual kind of fail-safe: the building’s main defence is the mountain’s climate, not its machinery.

How deposits work: the black box rule

Every depositing institution signs an agreement with the Norwegian Ministry of Agriculture and Food. The seeds are dried, sealed in airtight aluminium pouches and packed into standard boxes of 60 by 40 by 28 cm, which usually fly in as air freight. Every box is scanned on arrival, and storage is free of charge.²⁷ A sample averages about 500 seeds; Asdal gives the minimum as 500 viable seeds for mixed or cross-pollinating material and 300 for genetically uniform accessions.⁶⁷

Then the boxes go on the shelves and stay shut. Under “black box conditions”, no seed box or container stored in the vault is opened, the seeds remain “indisputably owned by the depositing gene bank”, and only that gene bank can ask for them back.² The Crop Trust compares it to a safety deposit box, and it’s a fair comparison: the bank never looks inside, and only the holder of the safe deposit box key gets the contents out.⁶ Checking whether the seeds are still alive is the depositor’s job too, using the duplicate kept in its own gene bank.²

Doors open for deposits three times a year on pre-announced dates, with special openings when needed.² The deposit of 17 June 2026 was the 70th since 2008: 15,387 samples from 11 gene banks in 32 boxes, including first deposits from Burkina Faso and Niger and 53 samples from Seed Savers Exchange in the USA. It took the total to 1,401,285.¹⁴

Withdrawals: when Aleppo’s seeds came back

For seven years the vault only took seeds in. Then the war in Syria cut the International Center for Agricultural Research in the Dry Areas (ICARDA) off from its gene bank at Aleppo; it had already moved its headquarters to Beirut in 2012. In September 2015 ICARDA asked for almost 130 of the 325 boxes it had deposited, which together held 116,000 samples of wheat, barley and grasses for dry regions.¹⁵ The Crop Trust lists it as the first withdrawal ever.⁶

ICARDA grew the seeds out in Lebanon and Morocco, and in 2017 it sent new seed back to Svalbard, the first re-deposit the vault had seen.¹⁶ Two more withdrawals followed in 2017 and August 2019. The last was 36 boxes: 31 of wheat and barley to Rabat in Morocco and five of clover, medics, pea, forage legumes and grasses to Lebanon. By then ICARDA had re-deposited 42,729 accessions, most of them grown from the seed Svalbard had returned.¹⁷ Asdal’s 2025 paper still names ICARDA as the only depositor to have withdrawn seeds.⁷

That’s the vault doing exactly what it was built for. It’s also the reason Fowler dislikes the word “doomsday”: the seeds came out because one gene bank had a very bad decade, not because the world ended.

The 2017 “flood”: what really happened

In May 2017 The Guardian reported that meltwater had got into the entrance tunnel, and the story went round the world as the doomsday vault flooding.¹³ The facts were smaller. Statsbygg said the water came in October 2016, during unusually warm and rainy weather. It got about 15 metres into the tunnel and froze there, while the seeds were stored far deeper in the rock. Two pumping stations at the bottom of the tunnel’s slope were already in place for water.¹³

“The seeds and the vault was never at risk,” said Hege Njaa Aschim, Statsbygg’s communications director. Fowler pointed out that the front of the tunnel had never been meant to be watertight, “because we didn’t think we would need that”.¹³ Asdal’s account, written later, agrees: water and melt had come into the tunnel in earlier years, October 2016 brought more than ever before, and the seed chambers were not affected.⁷

It wasn’t nothing, though. Statsbygg told High North News that the permafrost around the entrance had not formed as expected. It dug ditches to lead meltwater and rain away from the portal and set aside NOK 14 million for surveys and engineering, with a team led by the engineering firm Dr. Techn. Olav Olsen.¹⁸ Aschim called the situation “challenging, but definitely manageable”.¹⁸

The rebuild of 2018 and 2019

In February 2018 the government proposed a first grant of NOK 100 million for a new access tunnel in concrete and a separate service building outside the vault for emergency power, cooling units and other equipment that gives off heat.¹⁶ The parliamentary committee then recommended a cost frame of NOK 202.95 million for the project, at 2018 prices.¹⁹ Statsbygg also replaced permafrost material around the tunnel and laid frost tubes under insulating mats to keep the ground frozen, and expected to finish in May or June 2019.¹¹ Asdal records the watertight tunnel, the equipment building and new cooling machines as completed in 2019.⁷

Keeping water out of a strongroom is an old problem in our corner of history. Safe makers were patenting fire- and water-proof doors more than a century ago, such as the Meilink and Reynolds patent of 1903. Svalbard’s answer was bigger: move the warm machinery out and line the way in with concrete.

Can you visit the seed vault?

No, not inside. Only authorised personnel go in, and only on the dates when the vault is opened for deposits; it doesn’t even have its own staff.¹² Visit Svalbard, the local tourist board, is just as direct: the vault “is not open for visitors”. What you can do is join a guided trip from Longyearbyen that stops at the entrance, such as a two-hour sightseeing bus or a four-hour hike that comes down past the portal.⁸

So if you do make the trip, you’ll stand at the foot of a concrete wedge in the snow with the artwork glowing above you, about a kilometre from the airport, and that’s as close as you’ll get.⁸ Between mid-November and early March the sun doesn’t rise over Longyearbyen at all, so the lit-up portal is often the best view going.⁵ For the inside, the vault points everyone to a 360° virtual tour, which, as its own page notes, spares you the −18 °C.¹²

Svalbard has a second “doomsday” store a short way off, the Arctic World Archive, which keeps data on film in an old coal mine.²⁰ We cover both, with the Coca-Cola formula vault and others, in our guide to the strangest vaults in the world.

Seed vault vs bank vault

Judged as a vault, Svalbard turns most of the usual rules upside down. A bank vault keeps out people who want what’s inside; Svalbard mainly keeps out heat and water, and leans on remoteness and rock where a bank leans on steel. For the bank side of the comparison, see our explainer on how bank vaults work.

Seed vault figures come from the operators.¹²¹⁰ On the bank side, a Diebold and Mosler patent describes poured vault walls and the precast panels that replaced them, and a 2024 New York State specification calls for vault doors with combination locks and a time lock, and the FDIC requires the banks it supervises to have an alarm system.²¹²²²³ The grandest bank doors were a different beast: York’s 1924 advert for the New York Federal Reserve’s vault entrances boasted of six doors, each ten feet thick.²⁴ Svalbard’s builders had no need for that, because nobody is trying to drill their way to a box of barley.

The closer relative may be the Cold War shelter: a hole in the rock, built to ride out a disaster nobody wants. The difference is that the seed vault was built to be used in ordinary bad times too, as Aleppo showed. Our history of Cold War bunkers covers the ones built for the bomb, and our page on the Raven Rock Mountain Complex looks at one that is still in use.

Seed vault myths and facts

Sources for the pairs: Statsbygg via Popular Science and Asdal on the tunnel; the vault’s own pages on ownership and staffing; ICARDA’s withdrawals as above.^13721217 The Washington Post also checked the vault against some wilder online theories in 2016 and found nothing to them, along with no genetically modified seeds.⁵

Frequently asked questions