List the Most Common "Reality" Errors!

[ChickPea]

Thanks, J.Edward!

[Chick]

Here's something that I think I saw discussed once, but I'm not sure if this happens in nature often or if it's in the 'unlikely' category.

I see maps sometimes where there is a river that has its origin near the coast on one side of a continent, then it flows all the way across the land to exit into the sea at the other side of the continent. There is no mountain range or suchlike to obstruct the nearer coast. Is it realistic that a river would wind its away across a continent like that, rather than flowing towards the nearest coastline? (May as well pick your brains while I'm here!)

Yes, Larb posted just a few months ago about the Severn River which is about 200 miles long but the source is only about 12 miles from the sea!


That question had come up in my Calisdania thread, where I had a long river (required by the client) flowing parallel to the seacoast for hundreds of miles. For this very reason, I had put a string of hills along between the river and the seacoast to make it reasonable that the river didn't just flow to the nearest seashore.

[Chick]

2. Water always flow downwards towards the sea

Might be a bit clearer?

Good suggestion, Bobemor, definitely needs to be said many times.

Downhill is right, toward the sea is sometimes.

There is an excellent tutorial in Tutorials (a sticky) on How to Get Your Rivers in the Right Place. I expect I'll reference that for most of the river-related details.

[Chashio]

Actually, I thought it would be a good idea to include the exceptions; they're so fascinating and I know many of us gravitate toward mapping places that often don't fit into the norm. It would be cool and helpful, I think, to have them together--the usual and the unusual--with examples and explanations for why, when, how, what, where, etcetera, so that people can get a fuller sense and understanding of what is possible in the real world and make decisions about their settings based on a more complete view of those possibilities (and probabilities), without having to resort to asking whether or not the basic foundation of elements in their map is plausible or spending tons of time scouring the Internet for those answers when they may not know the terminology to find what they're seeking.

I know it is a large project (immense), but I just thought it would be fun and nice to put together a collection of illustrated guidelines (guidebook?) geared for mappers, with a map (or maps) of examples, some supporting information, and links to sources where you can learn more.

Maybe it's not a good idea, or unnecessary, or maybe it's even been done already--or it's just too much to put on the plate right now (I know I'm swamped at the moment)... but that is kinda what I was thinking, anyway. What do you think?

[J.Edward]

Now that would be a cool community project - the Guild's Guidebook to Mapping Environments!!
I like the idea of knowing what the rules are before you break them, but breaking them all the same.
If you can find 10 examples of a 'rare' occurrence it seems less rare, and then I'm okay with using it.
But i've always been a bit on the side of breaking rules.

[Meshon]

Would it be possible to edit the first post and add list items there? Then all the goodies would be right at the start and you could just include a note along the lines of "for discussion and exceptions, please see the rest of the thread."

[Azélor]

We could include something on how lakes form.

Meandering : someone posted a nice link in February : http://thebritishgeographer.weebly.c...processes.html
Accumulation of water in a depression, because of a river input or because of precipitation.
Past glaciations: only affect poleward latitudes, unless the whole planet froze at some point. It creates lakes but also valleys like fjords, making the coasts more rugged.
Also, poleward temperate latitudes will have the most lakes. Areas close to the tropics tend to have less precipitation and more evaporation but close to the poles, the evaporation rate is lower.
Outlets: Again as I mentioned earlier, not all lakes have outlets. I think they are common enough not to be considered exceptions. In fact, a lot of people think they are simply impossible. It needs to be explained, separately if needed.


A swamp can form anywhere if enough water is accumulated in the lowlands. A mangrove is different because it's made of partially submerged vegetation in salty water.
Deserts rarely form close to the equator since it's the wettest and most humid place on the planet. But it can happen in extraordinary circumstances.
Temperate latitudes must be very dry in order to turn into desert. They either need to be very far inland (Kazakhstan) or blocked by mountains (Nevada?) and even then, it's just a steppe.

Just some ideas...

And of course, one thing that newcomers always forgot (but I'm not sure if it's always relevant) is that they do not know what map projection they are using.

[Chick]

Actually, I thought it would be a good idea to include the exceptions; they're so fascinating and I know many of us gravitate toward mapping places that often don't fit into the norm. It would be cool and helpful, I think, to have them together--the usual and the unusual--with examples and explanations for why, when, how, what, where, etcetera, so that people can get a fuller sense and understanding of what is possible in the real world and make decisions about their settings based on a more complete view of those possibilities (and probabilities), without having to resort to asking whether or not the basic foundation of elements in their map is plausible or spending tons of time scouring the Internet for those answers when they may not know the terminology to find what they're seeking.

I know it is a large project (immense), but I just thought it would be fun and nice to put together a collection of illustrated guidelines (guidebook?) geared for mappers, with a map (or maps) of examples, some supporting information, and links to sources where you can learn more.

Maybe it's not a good idea, or unnecessary, or maybe it's even been done already--or it's just too much to put on the plate right now (I know I'm swamped at the moment)... but that is kinda what I was thinking, anyway. What do you think?

It's all fantastic ideas! Do we want a very basic guide for newcomers trying to do their first map? Or do we want an intermediate thing with descriptions of the exceptions? Or do we want a fully illustrated tome gathering together all the information in many of the existing tutorials?

I think the latter is a fabulous idea, but too complex and time-consuming for most of us.

I started out to do the first -- very basic do's and don't's guide for newcomers. I wouldn't mind including a tiny bit about exceptions, but mostly to point out how specific the circumstances need to be for them.

This thread can accumulate all the ideas you want, but for my part, I'll put together the very basic guide (maybe with mention of the exceptions, since everyone always wants to jump on them).

Volunteers for advanced versions are very welcome!!

[Chick]

We could include something on how lakes form.

Meandering : someone posted a nice link in February : http://thebritishgeographer.weebly.c...processes.html
Accumulation of water in a depression, because of a river input or because of precipitation.
Past glaciations: only affect poleward latitudes, unless the whole planet froze at some point. It creates lakes but also valleys like fjords, making the coasts more rugged.
Also, poleward temperate latitudes will have the most lakes. Areas close to the tropics tend to have less precipitation and more evaporation but close to the poles, the evaporation rate is lower.
Outlets: Again as I mentioned earlier, not all lakes have outlets. I think they are common enough not to be considered exceptions. In fact, a lot of people think they are simply impossible. It needs to be explained, separately if needed.


A swamp can form anywhere if enough water is accumulated in the lowlands. A mangrove is different because it's made of partially submerged vegetation in salty water.
Deserts rarely form close to the equator since it's the wettest and most humid place on the planet. But it can happen in extraordinary circumstances.
Temperate latitudes must be very dry in order to turn into desert. They either need to be very far inland (Kazakhstan) or blocked by mountains (Nevada?) and even then, it's just a steppe.

Just some ideas...

And of course, one thing that newcomers always forgot (but I'm not sure if it's always relevant) is that they do not know what map projection they are using.

Excellent ideas. I'll summarize them into short line items in the list, but eventually we'll want a little content to go with each item.

[Chick]

Would it be possible to edit the first post and add list items there? Then all the goodies would be right at the start and you could just include a note along the lines of "for discussion and exceptions, please see the rest of the thread."

Good plan! I'll do just that