Mars: The OTHER OD&D Setting

I've spoken before about implied worldbuilding, how fun it can be to tease apart the world that the rules of Dungeons and Dragons build. This has been done before for the setting of OD&D , and it's a fascinating read, but something that's stuck with me is the fact that the example for an alternate setting the players can venture into isn't some other plane, time, or even something like the…