Though graffiti is one of the oldest art forms with roots dating back to the Roman Empire, nowadays the street drawings suffer a bad reputation. Its detractors aren't completely unjustified in dismissing the art form -- often it's done in public places without permission and with little artistic appeal.
This, of course, it not always the case. Talented graffiti artists pour their hearts into their work and produce breathtaking pieces as a result. These works aren't always legal, but they can certainly be beautiful.
Below, find 20 works of graffiti art that make our planet a more colorful place.
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What do you think of graffiti art? Let us know in the comments.