Now, researchers are waiting to see if the Arctic will be hit by extreme heat again next winter, melting permafrost again.
That showed that the vault could serve its function, but hopefully there will be no need for another withdrawal in the near future. "It illustrates why we built it," Cary Fowler told my colleague Lydia Ramsey. "Loss of that collection would be irreplaceable. ... I tell people it's a great story — a sad story — of the seed vault functioning as an insurance policy."
In 2015, the ICARDA Seed Bank, which had been in Syria, withdrew samples from the vault — a first — so it could move and restore its seed bank, which had been damaged by war.
The seeds arrive sealed in foil and are kept inside sealed boxes to prevent any spoilage.
next slide will load in 15 secondsSkip AdSkip AdBut there's enough space in the vault's three main rooms to store 4.5 million samples, which would be more than 2 billion seeds.
So far, there are almost a million samples of food crops in the vault, collected since Svalbard opened in 2008. Each sample contains 500 seeds.
Generally, new seeds are moved to a trolley and rolled into the vault's main chamber.
The temperature inside is kept to -18 degrees Celsius, cold enough to keep the sealed seeds viable for — in some cases — thousands of years. But if the vault were to flood because of melting permafrost, no one knows what would happen. It could be a disaster.
The Crop Trust says that polar bears — which outnumber humans on the island — provide an extra "layer of security."
next slide will load in 15 secondsSkip AdSkip AdHere's the tunnel that became "like a glacier" when the meltwater froze. There are five doors with coded locks that anyone looking to get into the vault has to pass through.
The vault is supposed to be unlocked only for deposits, which happen three or four times a year. But now workers are trying to waterproof the tunnel leading in and attempting to create ways to channel water and melting permafrost away from the structure.
The rooftop and part of the facade of the building is a work of art with a light installation by Dyveke Sanne, since all public buildings in Norway are legally required to have art.
Seed samples are sent to Svalbard in large boxes, which are scanned with X-rays after they get to the island to make sure that they have nothing but seeds inside.
That way, the genetic diversity of crops around the world is supposed to be kept safe.
next slide will load in 15 secondsSkip AdSkip AdBackups are sent to Svalbard in case a disaster ruins the samples at the home seed bank.
The Svalbard vault is the central fail-safe for all those seed banks. If it fails, there's no backup.
The vault has seeds from more than 60 institutions and almost every country in the world, collected from over 1,500 global gene banks that store samples of seeds from crops native to the region they're in.
Since the vault is buried in permafrost, it's supposed to stay frozen at least 200 years, even if the power were to go out. But officials are worried. "Now we are watching the seed vault 24 hours a day," Aschim told The Guardian.
It's more than 400 feet above sea level, and there's little moisture in the air. But the Arctic is warming far faster than the rest of the world —faster than anyone expected.
next slide will load in 15 secondsSkip AdSkip AdSvalbard is the northernmost place in the world that still has scheduled flights, according to The Crop Trust, the group in charge of the global seed-bank system.