http://www.youtube.com/watch?v=Z77Z_G4iOyAA short movie clip that shows how the map makers are working on the map. The map makers are actually stage designers from theatre. First the whole place had been asphalted, then they draw some kind of a reference grid on it. To transfer the geometries onto the ground, they used around 270 stencils.
http://www.youtube.com/watch?v=SWmVbR16D6E