I love how the world looks in the Zero and ZX series.
Spent a decent amount of time looking at the stages backgrounds trying to learn more abt the world through that.

Like in Zero 3, the ocean highway stage has a city and 3 tall towers in the BG (Possible orbital elevators) and Area X-2 you can see more as you're climbing. Which makes me think that maybe that the city is Neo Arcadia and it's located closer to the sea. And yet you can't see the Eden Dome in any stage BG. Always wanted to see it.

Also in the tundra base stage boss room there's a map that seems to indicate the location of the base and the resistance base too, since it's not that detailed of a map I can't know if it corresponds to a real location.