Here goes the (not so) silly question! Sizes and dimensions!

[Morgan]

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...

[Joshua]

I would think that most fantasy maps use aspects of both. They're made to most accurately display any information that is critical. The work to get an absolute perfect representation of a fictitious place, though, is probably astounding. So some things are sacrificed to make the completion of the job more realistic. How much is sacrificed and how much is preserved is up to the individual, as you pointed out, but I think that by and large most fantasy maps are a mix of the two approaches. Interesting topic!

[Morgan]

Hmmm, yes, I think you're right. I'm wondering what degree of realism do people expect from maps of this type.
I mean, many fantasy maps are realized for fiction. Now let's take the example of a fantasy novel.
I don't think the reader cares how long or wide is that river, he cares only if the protagonist is strong enough to cross the river despite its width. And this puts all in perspective, of course.
On the other hand, if you buy a book and see a map of the world it's set in, you want to see a nice image. Perhaps you're not going to study the geography of the place, and you will use the map just as reference when your direction sense gets lost, but what you want as a reader/buyer is something cool to see. So the artistic map, cool and not necessary precise.
But, as a cartographer, what should one try to achieve?

[Gidde]

Interesting questions! I struggle with realism vs. ease/art a LOT (which is why my latest project is a flatworld: no projection pain). I don't really have much in the way of answers, but I'll be watching to see what the rest of the community has to say about this

[Jaxilon]

Well, for me, so far anyhow, I still consider myself more an artist than cartographer and that's because I am more interested in drawing and painting than I am concerned about precise GIS information.

That said, I would like to fake it as much as I can. I think most viewers are more interested in a map that sucks them in and allows them to get lost imagining what all those areas and locations must look and smell like. That's what I want to accomplish for the viewer anyway. I figure at some point I will be able to create what I envision more or less perfectly and then I will want to start making sure I understand all the serious real world details and so on but until then I'm not going to let realities get in my way

Obviously, hanging out in a place like this you can't help but start to pick up some of this stuff thanks to some of our more serious GIS type folks.

As far as scales go I think that often rivers are faked because they wouldn't even show up on the map otherwise. Personally, I like to show river locations and the scale is more about how far one city is from the next or how many days it will take to cross a mountain range. For a role player this is important to know and since I figure most my maps are for that purpose... If you measured the river using the scale however it might actually look like it's a half mile wide or something ridiculous. I'm ok with that but I try not to have it look too out of whack.

[Lukc]

I also usually take the side of art and topology, rather than necessarily topography.

For features ... average sizes and so forth ... I tend to rely on experience and places I've visited. If I imagine I need a river in the desert I might be reminded of the Nile, I'll go on Google Earth and measure it's width and a given location and so forth, to get an idea of the size. If I want mountains, I've been to different types and sizes of mountain, I go check out some typical mountains and measure them again. But ... this is more relevant for city maps, where I find some scale is more important than on a more symbolic, large scale map.

[Morgan]

So for now the general feeling seems to go in the artistic direction rathen that geographical accuracy.
I must say I agree, especially for fantasy maps. Perhaps one should consider the purpose of a map before deciding how much accuracy he wants to achieve.
As Jaxilon pointed out, most scaled rivers would not show up on large regional maps, but a fantasy novelist or a RPG narrator need that information, even if it's not accurate. In this context, less accuracy means more freedom to change things to fit the dramatic turns of the story, and that's ok. That's my vision, I'm glad to find so many others that think the same way.

Lukc, actually your advice is valid also for regional maps. I mean, I asked for average values so that in the process of building a semi-realistic world, I know how big can be certain features in the map, but perhaps the best way to do this is not to face the whole map at once. If I have a Sahara-like zone, I can delimit borders, and then use Google Maps to measure features in real Sahara. In this way I don't even need to ask myself where a certain feature can be. For example, if I see the Amazon river is the widest on Earth, how would I know if such a river can also exist in another climatic zone? Thanks for pointing out!

[Joshua]

I'm right with Jaxilon. Just... Not as far along the artistic road. But the viewpoints are similar. A map for an RPG or fantasy world or other piece of fiction should help to give definitive shape and dynamic to the mind of the player/reader. It should draw them in, make them wonder, and give them a solid foundation. So it should be an accurate representation, and therefore not so thrown to the wind as to shirk accuracy altogether (like the London Underground map).

If I'm viewing a fictitious map, I want to know a number of things. What's the location of this? How far is it from that? Which direction to here? What else geographically is around it? What's the terrain like, the climate, the fauna and flora? Most of these can be inferred or specifically shown on an artistic map. These things, for me, compile together to give my mind a clearer and hopefully more accurate image while I follow a character around on the page (or in the game). For me, that is the intention. After that, the more aesthetically pleasing the map is, the more fun it is to hover over it and study it. And I love spending that time with a great map. It can be as good as the story itself. It brings the world to life.

In these regards, I want some noticeable degree of realism. I want the designer/cartographer to take interest and show care with the details. But at the end of the day, it's still a work of art, and it still has a story to tell.

[Redrobes]

Its important to keep in mind what the map is for. With satellite images the rivers don't show up much. The Nile is about thousands of miles long but at its max is only 1 mile wide. The main issue is tho that for any RPG player character you cant cross a river if its wide and deep - esp if laden with horses and so forth. So the position of a river is vital to plotting a course across the map never mind that its trivially thin in comparison to the whole journeys distance in total. Large scale maps probably need to be more accurate about the sizes than regional and world maps.

[Lukc]

Agreed. Oh, and I think I just came across one of Redrobes maps: The Black God's War, or some such is the title of the book. Was that your work? (CORRECTION: it wasn't - my bad)

I think it's a good example of the need to convey vital bits of geographic information, even at the risk of being more conceptual then precise.

CORRECTION! I double checked, and I think the map was made by TheRedEpic. A certain adjective was responsible for my error.