Graffiti as a form of self-expression has been around for centuries. But sometime in the 1970s it became a subcultural revolution in urban meccas like New York where the walls of buildings, subway cars and other surfaces became an open invitation to creativity. While some consider graffiti a form of vandalism since it is often created without permission, its reputation has grown as an art form since the rise of graffiti-inspired artists like Jean-Michel Basquiat, Al Diaz and Kenny Scharf.

Somewhere along the way, graffiti art morphed into street art around the turn of the 21st century with such idiosyncratic talents as Banksy using cityscapes for provocative self-expression and subversive humor. The resulting global movement has become a rich melting pot of diverse styles and approaches. The following eight hot spots are ideal for viewing the best of the breed. Keep in mind that street art is transitory and ever changing and not guaranteed a permanent space at the locations listed below.

London

Easily one of the most controversial of all street artists is Banksy, who grew up in Bristol, England (the location of the featured image above) and relocated to London in the early 2000s. He is best known for a distinctive stenciling technique and aesthetic that provides alternative viewpoints to those offered by mainstream media such as his subversive treatment of icons like Queen Victoria. Some of his work can still be seen like “The Falling Shopper” on Bruton Lane to the east of Hyde Park, “Sorry, The Lifestyle.” near the Blackwall Tunnel and “TV through Window” on a car park wall between Old Street and Irvington Street. Other local artists include Stik (checkout the Shoreditch-Brick Lane area for his stick figure creations), Dscreet (famous for his signature owls in East London) and Malarky, whose bold, cartoon-like murals are all over postal code E1.

New York

What was once the stomping ground of underground art renegades like SAMO and graffiti-influenced artists like Keith Haring is now a sophisticated and cutting-edge mecca for some of the most sought-after street artists on the scene such as Now and Nosm represented above by “The Day After,” which was created on the Goldman Wall at Bowery and Houston Street in 2012. These identical twin brothers (aka Raoul and Davide Perre) were born in Spain, grew up in Germany but now reside in the city that produced such legends as freight train graffiti pioneer Zephyr (Andrew Witten), Lee Quinones (originator of the New York City Subway graffiti movement) and Phase 2 (Lonny Wood), famous for his bubble letters and abstract calligraphy. Some of the best locations to catch rising stars and current work is Freeman Alley on the Lower East Side, The Graffiti Hall of Fame in East Harlem, The Bushwick Collective in Brooklyn, The L.I.S.A. Project in Little Italy, Hunt’s Point in the Bronx and along the High Line.

Buenos Aires

There was a time when the main tourist attractions in Buenos Aires were the historic buildings, parks, museums like the Fundacion Costantini and the Bombonera stadium for a soccer match. In recent years, however, street art has become the new rage. Unlike most cities, there are few restrictions here on practitioners of the form and the result has lured world famous artists like Blu to leave their mark on the city while increasing the popularity of such local graffiti legends as Martin Ron, Jaz (Franco Fasoli) with his large scale murals featuring hybrid creatures and Gualicho (Pablo Harymbat), creator of retro-futuristic cityscapes inhabited by new forms of animals, plants and machines. Guided Street Art Tours are available or you can do your own exploring in such neighborhoods as San Telmo, the Coghlan Art District and Villa Urquiza, which was once full of abandoned buildings and is now a dazzling maze of gigantic, brightly colored murals.

Berlin

After the fall of the Berlin Wall in 1989, local and international street artists celebrated by adorning sections of the still standing wall with their art. It not only revitalized the city’s art communities but transformed dreary East Berlin neighborhoods like Mitte and Friedrichshain into showcases for some of the most vibrant graffiti art in Europe. Many people have probably seen “My God, Help Me to Survive This Deadly Love” by Russian artist Dmitri Vrubel, which depicts Leonid Brezhnev and Erich Honecker in a passionate liplock (the painting has since been removed from the wall). But dozens of other stunning works can be seen everywhere featuring the work of Johannes Mundinger, Alias with his unique stencil style depicting young boys or men in hoodies and XOOOOX, whose work often creates a dynamic between beauty (gorgeous fashion models) and ruin (the grungy areas where he tags his work). Other must-visit locations include the art-centric streets of Kreuzberg, Urban Spree and East Side Gallery.

Los Angeles

Graffiti and street art in Los Angeles have been on the rise since the '70s when skateboard culture embraced the “Wild Style” graffiti aesthetic and hangouts like Venice Beach and Santa Monica became meccas for the emerging subculture. While constant urban renewal keeps artists on the hunt for new areas and surfaces to utilize in this sprawling city, some of the most exciting new work can be glimpsed in the Arts District in downtown L.A., on side streets and walls along Melrose, Sunset and Hollywood Boulevard and in art venues like Lab Art, Known Gallery, Hold Up Art and LALA Gallery. Among the more famous local artists are David Flores whose pop art murals are distinguished by (in his words) a “stained glass" effect. Kim West has earned acclaim for her colorful wildlife and nature scenes which provide a stark contrast to their urban environment and Cleveland transplant WRDSMITH is famous for his wheat pastes and stencils with playful or thought-provoking typewriter-style text. Another standout is El Mac who uses photorealism techniques in his contemplation of Mexican and Chicano culture.

Paris

It is only fitting that the city that was once home for Henry Matisse, Paul Cezanne, Henri Rousseau, Pablo Picasso and so many more should be one of the pioneers in the graffiti/street art movement hosting such major talents as Ernest Pignon-Ernest (his silkscreen portrait paste-ups of poet Arthur Rimbaud are well known), Blek le Rat and his iconic life-size rat stencils and Monsieur Chat, the creator behind those mischievous yellow cats appearing on billboards, in the Metro and city streets. Head over to the Belleville, Oberkampf and Menilmontant districts to see the newest street art. Among the more current superstars are female artist KASHINK who often addresses political and social topics in her playful, Mexican folk art-influenced work, portrait specialist C215 (Christian Guemy) and Invader, who takes his name and stylistic influences from the video game Space Invaders and leaves his iconic signatures around the globe (The featured Invader work was created in London).

Miami

Unlike the other cities on this list, Miami is unique in this respect - you can experience all of the most exciting and compelling street art in one neighborhood, the Wynwood Art District. Once a seedy, undesirable area north of downtown, it was revitalized by real estate visionary Tony Goldman who unveiled Wynwood Walls to the public in 2009. The former warehouse district was filled with empty structures whose surfaces became giant canvases for visiting graffiti artists from around the world. The success of Wynwood Walls led to the creation of Wynwood Doors and Outside the Walls, art initiatives which have turned this neighborhood into an international tourist magnet. More than 50 famous street artists representing over 16 countries have had their work displayed on the more than 80,000 square feet of walls and include Lady Pink (Sandra Fabara), Logan Hicks, Peter Tunney, Retna and Swoon.

Sao Paulo

What was once a best-kept secret is now a known fact. Sao Paulo, Brazil’s largest city with more than 18 million people, has always been the industry and financial hub of the country but it is also a major art center with countless museums and galleries. Now it is quickly gaining a reputation for its exploding street art/graffiti scene. The neighborhoods of Cambuci and Vila Madalena, in particular, are hotbeds of creativity where you can see the work of such local visionaries as Os Gemeos (Gustavo and Otavio Pandolfo aka “the twins”), known for their streetwise social commentary employing colorfully-dressed, yellow-skinned figures. Nunca (Francisco Rodrigues da Silva) creates startling murals which confront modern Brazil with its native past while Cranio is famous for his anti-World Cup street art. The hip-hop influenced Speto favors woodcut style illustrations of tattoo art and street pamplets and the husband-wife team of Jana Joana & Vitche are renowned for their fantastical, folk art dreamscapes. Be sure to check out the mural walls at Beco do Batman (Batman’s Alley) and also visit the Museu Aberto de Arte Urbana de Sao Paulo.