Siri isn’t a very good companion on my journey to Sarrión. I’d been enjoying her mangled pronunciation of Spanish street names when giving me directions on the hired car, but once out of the city of Zaragoza, her instructions were to keep straight for 198km and she went silent. Driving through the huge empty landscapes of the province of Zaragoza towards the even emptier Teruel with not so much as a satnav voice to keep you company is a very quick lesson in just how empty rural Spain is.

Teruel is Aragon’s southern province and for the past twenty-two years, some of its inhabitants have been part of a pressure group called ‘Teruel Existe’ - Teruel Exists, which pretty much does what it says. For well over a century Teruel’s dry, rough, unforgiving terrain’s main export has been people. They have either gone to Spain’s major cities - I was once in a butcher’s shop in a village in Teruel many years ago at Eastertime and every customer that morning lived in the same area as me in Barcelona - or abroad, returning only for holidays, if at all. Sarrión is bucking that trend; a Teruelese village of 1,300 inhabitants at 1000 metres above sea level, it’s attracting its natives back from the cities and even recorded fifteen births in 2022, the only village in the whole of Teruel to do so. It’s all due to an underground fungi.

Estafania Doñate is waiting for me at the Manjares de la Tierra, a truffle shop and conservation business in the middle of the village. ‘This,’ she says pointing to the shop’s products, truffle sliced and conserved in oil, truffle preserved in brandy, fresh black truffle vacuum packed, jars of cream cheese with black truffle, ‘is what is keeping this village alive.’

Black truffle, tuber melanosporum, has always grown wild in this area but, unlike Perigord in France, it was only until recently that it was appreciated by its inhabitants. ‘My great grandparents called it the black potato and didn’t ever think much about it, but more recently we realised that not only was it an amazing product, but that here in a place where almost nothing grows is the ideal place to cultivate it.’

To grow black truffles requires a host tree, which the underground fungus can live round; in Sarrión’s case, the whole area surrounding the village over the past forty years or so has become fields of holm oak. All of the oaks start off as inoculated seedlings, allowing the fungi to grow in the root zones and they are planted and left for ten years to allow the truffles to start growing.

‘What happened here with the wild truffle,’ Estefania’s husband Marius tells me, ‘is that due to over hunting and also due to less human activity in the region as more and more people left, the wild black truffles grew less and less frequently and became harder to find, but by then we had learned how to cultivate it.’

Marius works alone in a field of holm oaks accompanied only by his English pointer, Cannoli. ‘You can use almost any type of dog to hunt truffles with,’ he tells me. ‘Training them can take any length of time from two days to more than two years – it completely depends on the dog. The main thing is to train the dog not to damage or eat the truffles.’

Cannoli runs round the field sniffing out mature truffles and scrapes at the ground and barks when he locates one. Marius then walks over to Cannoli to give him a treat to stop him scraping, and then with a knee cushion and a trowel, he gets on his knees and starts digging. ‘This is my job eight hours a day, five days a week during the truffle season, from 15th November to 15th March,’ he tells me. ‘When I am not digging I am checking the irrigation system, checking for pests - rabbits like both eating truffles and the water pipes, while moles dig holes as they come for the acorns and can disturb both the truffles and the pipes - and keeping the trees and the ground as healthy as possible for truffle growing.’

One person with a dog and a trowel can cover about five hectares of ground in a week and each active hectare yields about 80kg of truffles. The truffles are then sold to a processor, which cleans and categorises them. One of these processors is Doñate, which is owned by some of Estafania cousins, ‘I have ten first cousins, all of whom live here in the village. That’s unheard of in rural Spain, but we all make a living off black truffle,’ she says. Inside the tiny processor her cousin tells me that she is a qualified teacher but would rather live in Sarrión and have the quality of life she has there than teach in a school in another area of Spain. Later that day when I am in the tiny capital of Teruel I mention to someone where I have been. ‘Did you see how much care they take with the truffle and how well their village is doing? It’s amazing. Other places are trying to copy them but truffle is really hard to cultivate and it seems that Sarrión, the place where nothing could ever grow, is the best place for it.’

I thought about Marius in his field with a smile on his face pointing to the surrounding fields full of oak trees saying, ‘it’s as if we suddenly won the lottery,’ and I couldn’t help but agree.