Earlier this month, Inhabitat reported on a unique form of street art known as “Reverse Graffiti”, where, rather than the artist painting or wheat-pasting their creations, “they seek out soot covered surfaces and inscribe them with images, tags, and even advertising slogans using scrub brushes, scrapers and pressure hoses”.

This unique approach has become so popular that groundbreakers of the style like the UK’s Paul Curtis “have been commissioned by a number of brands, such as Smirnoff, who want to convey a sense of “clean” in an innovative way”, the article goes on to say.

Last summer, Brazilian artist Alexandre Orion (whose work is featured in the photos accompanying this post), scrubbed a beautiful series of skulls into the side of a Sao Paolo transport tunnel. Not only was the artwork visually stimulating, it served as a powerful reminder as to just how filthy and gritty the city’s urban landscapes had become. As a result, every tunnel in the entire city was cleaned.