Hand drawn maps: isometric donjon-castle and pyrenees area

[Lukc]

I think it's termed "isometric" as a synonym for "illustrated mountains without depth perspective". I've come across that use of the term before, I don't know whether it's correct or not.

[Hai-Etlik]

I think it's termed "isometric" as a synonym for "illustrated mountains without depth perspective". I've come across that use of the term before, I don't know whether it's correct or not.

Really it's closer to an oblique projection, though even that isn't quite right. Really it's just a symbolic representation with no particular projection being used to indicate a 3rd axis. (There may be a geographic projection in play but that's another matter)

Isometric has a very specific meaning, it literally means "same measure" because it preserves linear measures along three particular orthogonal axes. It's only really meaningful if what is being projected has three significant orthogonal axes (Very roughly, something "boxy") Any orthographic projection will preserve some set of 3 orthogonal axes, so it's only meaningful to distinguish a projection as isometric if there is some other significance to the 3 axes.