Land formation and drawing maps.
As I start another fun summer of roleplaying (figured out that I’m excited about that yet), I find myself drawing a map. For the longest time, Alyssa and I have used the same world, Isrlan, but now we are moving on and creating another.
Since she is much more busy than I am, I drew the map. But instead of drawing random things, I did a few specific details. In order to explain why this matters to you, I need to explain South Dakota to you first.

See the pretty river?
South Dakota is literally divided by the river, namely, the Missouri River, but since we abbreviate everything, we just call it the River. That makes East River and West River. For a traveler, that means mainly that when you cross the river you change time zones. For us in South Dakota, East River is mainly farming and baseball caps and West River is mainly cattle and cowboy hats.
But why?
In general, our weather moves from west to east. All our storms come from the west. To the farthest west point is the Black Hills (were Mtn Rushmore is). Mountains cause the clouds to rise, rain on the mountains, and give all the prettiness found there.
However, the clouds run out of water as soon as they over the mountains, so then they hit the Badlands. Personally, I find the Badlands incredible, because the dirt there is basically clay and there are many, many ridges, valleys and storm formations. I could spend a whole day there. (Or hide there with my secret organization that is taking down the government.)
Before too long, however, the clouds hit the River. This is where it is important, because the river fuels the clouds. The clouds suck up all the water, then move along across South Dakota, raining from the river onward and giving us our lush farmland. However, since we don’t get that much rain, we typically have hot, dry summers. (Expect for last year, but last year we broke record rainfalls.)
With that in mind, I made my map, keeping a river near the mountains to fuel the clouds, so my country doesn’t become a desert. See?
On another note, and I don’t know how this really plays into things, but if you look at my map, you can see a little river about half way between the border and the Missouri River. Besides the fact that “river” floods every year, a lot of weather alerts are determined merely by whether it’ll happen west or east of the James River (Or, since we abbreviate everything, The Jim.)