Hidden deep in the permanently frozen mountainscape of the world’s northernmost inhabited place, lies the ultimate agricultural failsafe for cities and populations around the globe: a remote vault with the capacity to store billions of seeds. A sharp decline in seed biodiversity – largely due to the fact that three-quarters of the world’s food supply comes from just 12 plant species, including major staples like rice, wheat and maize – has made preservation of seed and crop diversity more important than ever.