Once a year, the biggest names in world street art descend upon the small, sleepy Norwegian city of Stavanger to spray paint its buildings, walls and pavements.
Most of them began their careers painting illegally – most, in fact, still do from time to time – but here, the locals don't phone the police or complain, they embrace it. Welcome to Nuart: the most exciting graffiti festival in the world, held in the most unlikely of locations.
Stavanger, on the west coast of Norway, is known for its wealth since "winning the lottery" in 1989 when an oil rich seabed was discovered ten miles from the mainland.
With the liquid gold came rapid industrial development and international business, making it one of the wealthiest cities in Scandinavia.
Striving for equal cultural wealth, the landscape of raw industry is the backdrop for the relatively young Nuart festival, now in its 8th year.
Walking the streets this year, festivalgoers will stumble across, among other things, a blindfolded 40-foot high angel (from Cape Town artist Faith47), a whale with oil spurting out of its blowhole as it lays sliced in half (a controversial nod to Stavanger's oil-rich legacy, by Belgium's Roa) and an exotic Russian doll (from Newcastle-based artist Hush).
Then there is this year's highlight; Stavanger's air traffic control tower painted by M-City, all 600 square metres of it.
The layers of sweeping blue tones and black stenciling stand as a welcome beacon to the incoming international flights. This is the benefit of showcasing street art in a small city: imagine the bureaucracy involved to do this at Heathrow.
Nuart founder and director Martyn Reed is the man responsible for turning Stavanger into a focal point for world street art.
Originally from London, Reed moved to Norway in 1997 as a DJ and created a music festival in 2000, adding digital art to the mix the following year, thanks to generous arts funding.
It was when Reed was getting out of a taxi in Shoreditch, London, that a Banksy art piece caught his eye; the stencilled monkey with a sandwich board stating: 'laugh now, but one day we'll be in charge.'
"It didn't register that it was fine art at the time," Reed says, "but it was the first time I found an art that resonated with me to the bone."
Reed returned to Norway, determined to bring the underground and fresh artistic form to Scandinavia.
But after Nuart's change of emphasis from digital art to street art in 2005, all government funding was withdrawn.
Undefeated, Reed marched to the bank, took out a loan and ploughed ahead alongside his artists, hitting the town with illegal street art.
Stavanger loved it. With the public won over, political and financial backing soon followed.
It's hard to imagine a public reaction like this in Britain. So why here? "Norway is a social democracy and they've really accepted alternative voices." Reed says, "Norway doesn't come with all the negative baggage attached to graffiti culture, like everywhere else."
Unlike, say, LA, where much of this style of art originated. Without the stigma of criminality, the work has been free to be judged in Stavanger on its own merits. No wonder Nuart has proven such a peaceful haven for artists like Saber and Hownosm, who spent much of their earlier career hiding from police helicopters.
A trip to Nuart challenges the way you look at cities, and in doing so, achieves one of the central aims of street art since its origins. Returning to London, you find the stencilling of 'Mind The Gap' on the underground platform appears brighter than before, and derelict buildings seem to cry out for a splash of colour. If you look hard enough, there are canvasses everywhere.
Nuart 2013 runs until 20th October