Johannesburg: the city that's a giant art gallery

Johannesburg in South Africa hosts the annual City of Gold Urban Art Festival. Rasty Knayles, one of the co-founders of the festival and of the Grayscale Gallery, and gallery curator Jared Pereira are passionate about the positive role graffiti art can play in public life, transforming no-go areas and creating free public art spaces for South Africans who don't have access to art.