Electricity comes from four large solar panels, and thanks to careful use, the Stewarts live with all the mod cons, except air conditioning. “We’ve become naturally parsimonious, and always switch everything off when we leave a room,” Stewart says. “But we have all the electricity we need to run our food processor, bread-maker, lights, computer and hi-fi.” Music is important to Stewart, who was the first drummer in Genesis, and plays classical guitar.

Visitors to El Valero could be forgiven for thinking that life in the Alpujarras is a bed of roses, but the idyllic life disguises a harsher reality. “Farming here is purely subsistence,” Stewart warns. The income from his books has made life more comfortable than it was when he eked out a living from farming, selling seeds gathered from wild flowers and shearing sheep, locally as well as further afield in Sweden. “We would still be here without the books, but living very frugally,” adds Annie, who worked as a shepherdess and horticulturalist before they moved to Spain.

So how do their fellow British expats survive? “There are quite a few alternative medicine types about, but I don’t know who their patients are,” Annie says. “There is a cannabis festival nearby every year, so there is some home-grown business, but it’s small-time. Then there is renting out cottages, but most of all people seem to live off vast profits from selling up in the UK.”

Prices have surged in the two decades since the Stewarts bought El Valero for £25,000, though the market is slowing down. “Prices in the Alpujarras rose to ridiculous levels,” says Annie. “Ten years ago, a Dutch couple bought a farm over the river for less than €100,000, and sold it a few years ago for €600,000. Asking prices are still crazy, though I’m not sure anyone is paying them now.”

Stewart’s first book, Driving Over Lemons, published in 1999, may be funny and inspiring, but it is also a guide to what you shouldn’t do when buying property in Spain. “We did everything wrong, but it turned out okay,” he admits. “We bought without checking anything, and we bought on the ‘wrong’ side of the river, which turned out to be a blessing. This place has brought us nothing but luck and joy.”

He does have practical advice for people thinking about buying a home in rural Andalusia, though: “Stay in the area for a year before you buy. Live through all the seasons, get to know the people, and get to know about water. In this part of the world, the three rules for buying are not ‘location, location, location’, but ‘water, water, water’. ”

Chris Stewart’s new book, Three Ways to Capsize a Boat: An Optimist Afloat, is out now (Sort Of Books £10.99)

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