Nomenclature of places
This planet is filled with a massive amount of land (even if it pales in comparison to the area covered by water bodies, it is quite a lot). Even the mere thought of having so much area around is really fascinating, and covering all of it is quite a daunting challenge - but that notwithstanding humans have managed to inhabit a significant amount of land collectively and have arguably flourished over so many centuries.
A by-product of this is the system of naming various locations on the planet - not only countries and districts and cities, but even streets and lanes within them! Along with these, quite a few natural formations have been named, whether a lake or a mountain peak. There’s almost nothing (of significance, arguably) that hasn’t been given a title of some kind!
Some names can be understood quite simply - take Grand Canyon for instance - it is called so because…it is a grand canyon. Or the Panama canal. But when it comes to some examples like Moscow or Canberra, or some very local name like “Chapman street”, the explanation starts becoming more interesting. It’s really a task to trace these names and to think of how they came to be.
There’s an entire page on Wikipedia devoted to this topic. I’m glad it exists.