Hydromancerx
C2C Modder
In France, they are so common, that a lot of them are still is use. Some for wine, some for fungi and some... still for housing!
Spoiler :![]()
So, caves can be require for a lot of thing, even modern one (the BatCave)
Yeah but if I had an Earth map I could probably represent the caves of France in one tile. Then again France on an Earth map may only be between 3 to 10 tiles. Depending upon the size of the map.
EDIT: Then again I may be digging myself into a hole.

But yeah a lot of other things are much more common than caves yet are represented as terrain features, resources or even terrain itself. I think it just comes with the territory when it comes to civ4 maps.