Some of the world's most creative artwork lives - often temporarily - on buildings, walls, and sidewalks.
Travel website Travel and Leisure has come up with a list of the best cities for street art. Reuters has not endorsed this list.
"Street art can change your relationship to a place," said Marc Schiller, cofounder of WoosterCollective.com, a website devoted to street art. "It opens up your peripheral vision, so you start to notice things you didn't before."
1. Los Angeles
Some of Los Angeles' best spotting grounds are in La Brea, particularly North La Brea Avenue around Melrose Avenue and Beverly Boulevard. Banksy - easily the world's most famous street artist - has left his mark here in several spots just outside the Beverly Cinema. You might also see Warhol-style colorized photo portraits from relative newcomer MBW.
In the 20 years since the demolition of the Berlin Wall, street artists have been steadily invading the city's easterly districts, particularly the neighbourhoods of Mitte, Kreuzberg, and Friedrichshain where the longest-remaining piece of the wall still stands. Look for striking stenciled figures from artists Alias and Xoooox and the signature, spray-painted shaking fists of native Berliner Kripoe.
In Chelsea, the city's main gallery district, the block of 21st Street between 10th and 11th avenues is a good place for street art. The walls outside and across from the Eyebeam Gallery are almost always thickly decorated. Look for intricate wheatpaste designs which are painted, drawn, cut out, and then affixed like sheets of wallpaper, from street artists like Gaia, Imminent Disaster, and Swoon and bold posters from Shepard Fairey and Dain; and mosaic-tile aliens and robots from Invader. 4. Brooklyn, New York City
Prime viewing areas include North 6th Street, Ainslie Street, and Roebling Street where a towering radio-controlled giraffe by artist Nick Walker decorates a wall. Look for comic-book-style poster art from Faile, gorgeously colorful photo collages from Judith Supine, and woodcut-style stencils by C215.
5. Sao Paulo
Head to the hip neighbourhood of Vila Madalena, on the city's western edge where the famous Beco do Batman is covered with an ever-changing display of artwork. Look for works by hometown street-art heroes like the striking woodcut-style murals of Speto and Nunca and the dreamy, yellow-tinged figure paintings of Os Gemeos (twin brothers Otavio and Gustavo Pandolfo).
The working-class enclaves of the East End, especially the multi-ethnic neighbourhood around Brick Lane and the adjacent industrial quarters of Shoreditch and Spitalfields, are good for street art. Look for Shepard Fairey's dramatic, propaganda-style posters in his signature colours of black, red, and white and accompanied by his tag, Obey (Fairey shot to fame in America with his now-iconic Obama poster).
7. Melbourne, Australia
With its thousands of laneways or alleys, Melbourne has become a mecca for enthusiasts of stencils, murals, wheatpastes, and poster art. Hosier Lane, in the central business district, is completely and perennially festooned. Look for deftly painted superheroes and looming, distorted faces by Anthony Lister and glamorous photographic close-ups of women's faces from Rone.
While two of the world's most famous street artists, Blek le Rat and JR, hail from Paris, their work isn't often seen these days in their hometown. But fans can try their luck in the 20th Arrondissement neighbourhoods of Belleville and Menilmontant. More easily accessible art can be found in the bohemian-chic district of Le Marais. Keep an eye out for Jef Aerosol's stencilled portraits of musicians or Invader's tile aliens and Pac-Man-style ghosts.
9. Buenos Aires
The most reliably excellent work is in the adjacent neighbourhoods of Belgrano and Palermo. Works by homegrown talent, like the friendly, cartoonish murals by Doma collective, are all over but sleuths should also track down the monumental installations from famed artist Blu.
10. Bethlehem, West Bank
Here, along a wall that functions as a cultural as well as physical barrier, artwork seems to speak more loudly. Several prominent street artists who decorated the wall as part of a 2007 exhibition still have work visible, among them Banksy, Swoon, and Blu. But just as striking are the long-limbed painted figures by Israeli artist Know Hope and JR's series of photo portraits of Israelis and Palestinians seen side by side.
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