My reference image (pictured below, left) is a scene from the show "Avatar: The Last Airbender." It's from season 2, episode 6 titled "The Blind Bandit." It's more or less a stadium for fighting. The main primitives I used were cubes, cylinders, and other quadrilaterals. The biggest challenges were sizing and getting things to fit together and match each other. And since it was a fictional scene, I didn't have real-life measurements to compare it to.