Here’s a fun detail that’ll make you feel like a film nerd: the Emerald City’s green hue was achieved with color filters and lighting, not paint. The sets were actually white and gray, but they used harsh green gels on the lights to tint everything. It saved time, and it made the city look impossibly vibrant on Technicolor film.
Also, the roads? They weren’t yellow bricks. They were painted plywood laid over tar paper. When actors walked, you could hear a hollow “thwack” if you listened closely. The sound department had to mute it later. Ironic, since the whole movie is about following a road that is not really a road.
Step Inside Old Hollywood’s Most Iconic Movie Sets | Architectural Digest
