On a bright, autumn Saturday afternoon, on a patch of pavement in front of the rather humdrum environment of a retail shopping park a few miles from Athens airport, two young men sporting hoodies and scruffy facial hair are putting the finishing touches to a stretch of canvas. Clutching spray cans and rolls of masking tape, they step back from their work, revealing a mishmash of abstract, graphic designs in bright yellows, greens and pinks. Around them, a crowd of people applauds, celebrating the intensity and energy that has gone into their performance. The two men smile sheepishly, unused to working in front of an audience, or in full view. Both are street artists, who’ve spent the past few years covertly putting their marks and designs on walls and buildings without the owners’ permission. 24-year-old ‘Opium’, all brown cords, straggly beard and Vans, is an Athens native, while his half-French half-Greek friend, ‘Cacao Rocks’, is 25, and sports glasses with fashionable electric blue frames, and a moustache that twirls up at the ends. Now, they are freely indulging in their craft in public.

In Greece’s capital city, street art has recently moved above ground from its subterranean roots, thanks to the launch, in 2013, of its very first street art festival. It was the brainchild of 39-year-old Andreas Tsourapas, himself a street artist who goes under the name LosOtros, and came about in response to the recession. “In 2012, I was disillusioned with how things were,” he says. “I wanted to show people that the Greeks can be resourceful and organised; that we’re not as the media had painted us. And I was keen to bring some light and colour back to the country.”

A sleepy-eyed, slightly rumpled-looking figure with grizzled five o’clock shadow, Andreas’ appearance belies a steely core of determination. Once he’d come up with the idea, he spent the next 18 months – as well as a significant chunk of his savings – getting the project off the ground. “I used to live in Paris, and was involved in the street-art scene there, so I knew a lot of artists outside of Greece. We invited 29 street artists, both local and from different parts of Europe, to come and make art over a month, from June 2013. We couldn’t pay them, but we covered the costs of their flights, accommodation and materials.”

Artists came from as far afield as Israel and Switzerland, with Andreas directing operations. As in most countries, street art is seen as criminal activity in Greece, resulting, at best, in a large fine, and at worst, jail time. Andreas’ challenge was to get local government on board with his plans; and the municipality of Nikaia, a traditionally immigrant and industrialised suburb to the west of the city, gave permission for the artists to use several

of its high schools for the purpose.

“I made the point to the mayor that getting the walls decorated in art – for free – would save them thousands in maintenance costs!” he laughs.

A drive around the area with Andreas and his friend Maria Kappatou, a visual artist, proves that his original aims have succeeded on both counts; vast, sprawling, colourful images, some more than 6m high and wide, attract the eye and brighten an otherwise ordinary neighbourhood. And the willpower required to marshal so many artists, some with big egos and their own agendas, has nonetheless resulted in 14 schools, and over 13,500m², being decorated. But ultimately, what Andreas wanted to achieve was getting artists to collaborate on works together. “Street art has always been a solitary pursuit,” he says. “Everyone has their own style, and their own patch, and works in isolation. I wanted to create dialogue between artists; bring together rivals who don’t normally talk. I want to foster unity in the street art scene, and ultimately, I’d love to see unity within Greece too. In Greece, people don’t talk to each other about difficult issues – that’s one reason why we have so many problems.”

There are primary- and pastel-coloured graphic abstract shapes, more recognisable forms, and images of people – from a side profile of what looks like an African warrior, to a woman in a ’50s-style circle skirt doing swing dance. Some designs are more playful than others; a massive bunny sporting phallic-shaped ears and chewing a carrot, Bugs Bunny-style, by local artist Billy Gee, adorns one wall. Others have more of a message; a Swiss artist, BANE, has created a powerful image on the side of a different school. Against the blue-and-white backdrop of the Greek flag, a giant lion snarls, exposing its sharp teeth.

“This represents Greece,” explains Andreas. “It says that we were hurt and wounded, but now we are defiant and roaring back to life.”

Local and national media seized on the inaugural festival, and for 2014 Andreas decided to make it a year-round affair after he was approached by the owners of Smart Park, the retail area outside the city centre, which now hosts live painting demos every Saturday. Attracting crowds in their thousands, it’s another way for artists to showcase their work and to help the public understand the process. “Greeks painted on walls in ancient times,” says Andreas. “This is just a revival.”

Several more schools have been painted this year, and this year he hopes that more artists will come and add to what’s already been done, so it can evolve. The festival has had a wider impact on both Greece and the artists. “It’s given a platform to people, and brought street art into the mainstream. There are now 15 or 16 smaller festivals throughout the country, in places like Mykonos and Kalamata, who ask for our input and advice.” Adds Andreas: “It’s created admiration and acceptance, and led to the partial legalisation of street art here. I want to give people a way to make a living from their work.”

In the upscale neighbourhood of Kolonaki, where designer boutiques rub shoulders with five-star hotels, is high-end art gallery Aenaon. All cool cream marble and spotlit canvases, its owner and dealer George Tzilalis, an elegant man in his sixties, hosted his first ever show featuring street art in May. The artists who took part included BTOY, who uses airbrush techniques to create beautiful, colourful pop-art style portraits of women, and FKDL, a French artist who works with collage. “Smaller artworks can sell for around €1,200 [£950],” says George, “larger ones for €2,000 [£1,500].” It’s a long way from spraying images on to shopfronts under the cover of darkness. These days, thanks to their higher profiles, street artists are landing commissions for bar, hotel and restaurant interiors, as well as for private residences.

But going mainstream comes with its own set of problems. In the narrow, hip backstreets of Psiri, a bohemian neighbourhood just behind the main thoroughfare of Ermou, Athens’ most popular shopping street, is the city’s only urban art gallery, Sarri 12. Curated by painter Antonakis Christodoulou, it opened in 2013, and shows there’s more to street

art than just tagging and graffiti.

Down a steep set of stairs next door is Opium and Cacao Rocks’ studio; a chaotic, colourful space, they’re preparing for their own solo shows and both are candid about working underground versus going mainstream. “On one hand, you can develop ideas better and in more detail, taking more time,” says Opium. “But sometimes having your work in a gallery is boring,” counters Cacao Rocks, who cites ’80s urban artist Keith Haring as one of his influences, “and you want more than just an elite few people to come and see it. You want it to be outside, on show for everyone. It’s about compromise.”

Later, I take a tour of some of the up and coming areas of the city with Nathalie Kontou and Anthia Vlassopoulou, two Athenians who set up Athens Insiders, which offers bespoke tours. Like so many young people, they lost their jobs during the recession. “The crisis has made people come together and collaborate more,” says Nathalie. “There’s a big crowdfunding scene here now, new bars and businesses are springing up all the time. The 2012 demonstrations led to communities working together to try to get what they want.”

On the outskirts of achingly fashionable neighbourhood Gazi – named after the local decommissioned gasworks, which in the last couple of years has sprouted nightclubs and neon-signed bars like mushrooms – one huge wall next to a main road is covered with a massive painting, which is by local artist iNO, a fine art graduate, like so many of the street artists. The painting is a massive eye watching over a robotic figure, which is trying to run away.

It’s powerful and disturbing at the same time, and it reminds me of something Andreas said earlier: “Street artists are not here to entertain. We’re here to stir things up.” Job done.

Essential info:

Flights from London to Athens direct cost from £122 with Aegean Airlines. Visit aegeanair.com for details and to book. A double room at Hotel Alexandros costs from €99 [£78] per night. To book, visit airotel.gr/hotel/alexandros

To find out more about the Athens Street Art Festival, visit athensaf.eu. Its forthcoming app will detail all the sites the artists are working on, so you can visit them yourself. For a tour of street art in Monastiraki and Psiri, visit dopios.com/experiences/greece/athens/1076-street-art-tour-in-monastiraki-and-psiri-area. Tailored off-the-beaten-track tours with Athens Insiders are available.

Visit athensinsiders.com, and to find out more about Athens, and the rest of Greece, visit discovergreece.com