The street art festival is in its second year, and already running out of wall space.
"We want people to reflect on the contemporary city and the kind of life we live -- where nature is not present -- through art."
Graffiti artists gathered in Grajaú this month to paint the walls anew.
There are 45 new murals, and 90 newly inspired young artists.
Because public canvases can do a lot more than brighten a wall.