Ok, I was wondering about different map types. In the Carthography page on Wikipedia, i read:
A topographic map is primarily concerned with the topographic description of a place, including (especially in the 20th and 21st centuries) the use of contour lines showing elevation. Terrain or relief can be shown in a variety of ways.
A topological map is a very general type of map, the kind you might sketch on a napkin. It often disregards scale and detail in the interest of clarity of communicating specific route or relational information. Beck's London Underground map is an iconic example. Though the most widely used map of "The Tube," it preserves little of reality: it varies scale constantly and abruptly, it straightens curved tracks, and it contorts directions. The only topography on it is the River Thames, letting the reader know whether a station is north or south of the river. That and the topology of station order and interchanges between train lines are all that is left of the geographic space.[17] Yet those are all a typical passenger wishes to know, so the map fulfils its purpose.
So, while a topographic map tend to maintain geographic accuracy, topological maps deal with simpler information, and that is perhaps the best choice for calligraphic fantasy maps.
But, if this is the case, why do calligraphic fantasy maps often include a scale? Is the distance between two points the only information that we can recover from the scale?
I know, this mainly depends on the map creator, but I was wondering what is the general idea about this topic.

Also, I wanted to ask, does anyone know about some resource out there that gives average dimensions of Earth's features? For example, rivers lenghts or width, mountain heights or base widths.
I can easily find the greatest/largest/longest/widest features, but something tells me that the average is not easy as calculating half the maximum...