A huge mural dominates the Olympic Boulevard in Rio. The artwork shows the faces of five indigenous people from five continents. The themed creation, stretching 3km, is the work of Brazilian graffiti artist Eduardo Kobra. It took about 100 gallons of white paint, 1,500 litres of coloured paint and at least 3,500 cans of spray paint. The 190-metre-long artwork captures the colour and vibrancy expected at Rio 2016.