My first attempts at worldbuilding were pretty bare-bones worlds for my magic systems to live in. I don't really remember very much of them (apart from the fact that they all had Inca and Aztec expies), and the documents are either deleted or buried deep in my Google Drive.

My first attempt at making a world for its own sake resulted in a medieval-ish fantasy world. Humans and fish people were the only sentient races. It had some pretty neat stuff (if I do say so myself), like Aztec pirates, a steppe empire that used to be ruled by a settled theocracy in a giant tower, and a creature from another universe that looked like a giant pile of flowers. On the other hand it was really disjointed and inconsistent and had an over-complicated and ever-expanding magic system that was pretty much used to justify having a bunch of other magic systems. I've still got all the documents for this one.