Add more fields to cities (and some more questions)

Hi,

Is there any way to add more fields to cities ?
We would like to add a TinyMCE description, and some other fields with administrative details.

I can’t see any hook I could use and I’m not able to use ACF either…
Also what exactly is a location : A CPT ? A taxonomy ? Both ?

We thought we could use a “city” CPT with CPT Addon to add these cities and to link them with actual places or events, but thinking of it, it looks very complicated to achieve…

Regards,