Yarn bombing, also known as guerrilla knitting, is a type of street art or graffiti using items made from yarn - whether knitted, crocheted, or made into pom-poms.

BBC: Left Lion in Nottingham is 'yarn bombed'

Meanwhile, over the past decade or so, a concentration of cutting-edge galleries - featuring everything from SoCal's native lowbrow street and graffiti artists to Japanese pop-art imports - has reclaimed an industrial area on Culver's eastern edge, creating an arts district to rival New York's Chelsea neighbourhood.

BBC: Culver City, ready for its close-up

That first effort was self-consciously hip, a place to hang, chat and read about graffiti "art" and South African street styles.

FORBES: Digital denim

Gabriel Schoenberg, CEO of Graffiti Tours New York, called Five Pointz one of the most significant street art establishments in the world.

BBC: Urban art attracts tourists