Mapmaking, Geography & Science!
Updated: Jul 7, 2021
There is a very obvious connection between mapmaking and geography and this little article is going to talk about how you can use things like geography, geology, weather patterns and our understanding of science in general to create great looking maps full of interesting features!
Here's a quick little definition of what a map is from dictonary.com: “a representation, usually on a flat surface, as of the features of an area of the earth or a portion of the heavens, showing them in their respective forms, sizes, and relationships according to some convention of representation”
So already there is a lot of vague wording here and every map is simply trying its best to represent a world as best it can. Even satellite maps on earth, while tremendously accurate can't emulate real life as that wouldn't be practical or even necessary. Instead we want to look at some of the best known examples of geographic features on earth and try to understand why they are like this in order to translate that over to drawing a fantasy map.
While this list is not exhaustive, hopefully it can help someone new to mapmaking create a more solid base for a map.
Tectonic Plates
This is the main reason earth looks the way it does. Instead of a solid crust, earth is comprised of a series of smaller parts or plates that smash together, pull apart and grind along one another at incredibly slow speeds over millions of years. This changes the position and shape of the continents and oceans and affects all the other things I’m going to talk about in this article.
For this to help with making a map, the first thing you need to understand is that the shape of tectonic plates are not governed by any particular rules, at least on earth they formed at some point if the very distant past pretty much randomly in shape. You can make a bunch of winding weird scraggly lines all over a piece of paper and connect them to make the plates you need. But if your having trouble remember plates are usually larger than continents and just as random looking.
After you have a few plate lines on some paper you now need to understand the different types of fault lines along the edges of your plates, these are very useful!
Transform boundaries occur where two plates slide, or perhaps more accurately, grind past each other along transform faults, where plates are neither created nor destroyed. The San Andreas Fault in California is an example of a transform line. These typically dont make volcanoes, but are hotspots for earthquakes!
Divergent boundaries occur where two plates slide apart from each other. At zones of ocean-to-ocean rifting, divergent boundaries form by seafloor spreading apart, allowing for the formation of new ocean basins. Africa's East African Rift and Valley and the Red Sea, are examples of divergent boundaries.
Convergent boundaries occur where two plates slide toward each other to form either a subduction zone (one plate moving underneath the other) or a continental collision. At zones of ocean-to-continent subduction. The Andes mountain range in South America, and the Cascade Mountains in Western United States are examples of convergent fault lines.
You can add these different types to the lines you have created with arrows. As an example I found a continent generator and created a supercontinent, I then put an overlay over it to make my own simple tectonic plates. You don't need to worry too much about what lines go where, the exact nature of why a line is either Transform, Divergent or Convergent is mostly random and doesn't seem to follow any specific rules. At leastits not worth worrying about in a fantasy world at any rate.
Tectonic plates can do alot for your world beyond mapmaking but perhaps the biggest advantage it can have is that you can now place down mountains and volcanoes in very realistic ways on the map. The himalayas for example are a huge mountain range on earth because the Indian plate is sliding under the Eurasian plate creating a buckle in the earth that rises up forming a mountain range. The Andes in South America are another mountain range that is very obviously created by plate tectonics in a similar fashion as a plate slides under the south american plate.
Volcanoes are also very likely to occur around fault lines and can add some nice features to a world or region map! If you have your tectonic plates worked out roughly you know pretty much where to put them!
Temperature Maps
If you are starting the map making process for a whole world or region and are not sure where to put down forests, deserts and jungles etc then the best thing you can do is look at temperature maps. Overlaying something similar on top of the continents you might have made will mean you can quickly figure out where cold and hot areas will be and give you a better understanding of the climates, biomes and environments. On earth the temperature map is based upon a whole host of things and is not uniform across the globe.
But to give a good example of how this might work, below is a simple uniform temperature map with our supercontinent and you can now clearly see where the cold areas of the map would be, where the really hot areas are and most likely in this specific case a massive super desert on a massive scale in the middle but that's another story entirely!
Of course you can make your own temperature map and make it colder or hotter depending on your world and what kind of map you want!
Weather Patterns
On earth our weather patterns can be just as important to why a region is hot or cold than its overall position on the temperature map. You can study weather patterns in more detail to create some weird and wonderful environments for a fantasy world and I will cover just a few here.
Wind
Wind doesnt normally cause environmental change on a large scale, at least not enough for it to be worth it for a fantasy mapmaker, but there are a few expectations. The biggest real world example is the dust and minerals in that dust from the Shahara desert in Africa blowing across the Atlantic providing essential fertilizer for the Amazon rainforest where it compensates for poor rainforest soils. The Amazon might only exist in its current form, thanks to the winds coming from another continent. Worth bearing in mind for fantasy maps anyway!
Rain Shadows
A mountain range typically creates a dry area on the side opposite a body of water like an ocean or sea. The mountains block the passage of rain-producing weather systems and cast a "shadow" of dryness behind them. Wind and moist air is drawn by the prevailing winds towards the top of the mountains, where it condenses and falls before it crosses the top. This also means that rivers almost always form on the sides of mountains facing the oceans of a world with very few exceptions.
Ocean Currents
Huge moving bodies of water, currents are critical for the health and movement of oceans and without them the oceans would stagnant. Ocean currents also influence the temperature of the regions through which they travel. For example, warm currents traveling along more temperate coasts increase the temperature of the area by warming the sea breezes that blow over them. Perhaps the most striking example is the Gulf Stream, which makes northwest Europe on earth much more temperate than any other region at the same latitude.
This can make a big difference when creating a coastal region and doesn't need to be very detailed, a simple does a warm or cold current run along the coast or not might help define how that region looks overall.
Now our little map has some ocean currents, we can start adding in some simple biomes and environments!
Rocks!
Not something many people think about when creating a map for a fantasy world lets be honest.. The type of rock can be critical though in the formation of many unique and interesting features like canyons, cliffs, waterfalls, underground caves etc.
Sedimentary
Sedimentary rocks are formed from particles of sand, shells, pebbles, and other fragments of material. Generally, sedimentary rock is fairly soft and may break apart or crumble easily. You can often see sand, pebbles, or stones in the rock, and it is usually the only type that contains fossils. An example of a sedimentary rock is limestone and this of rock is soft enough for water to run through over time creating huge tears, rifts, canyons, underground cave systems etc.
Metamorphic
Metamorphic rocks are formed under the surface of the earth from the intense heat and pressure. The rocks that result from these processes often have ribbon like layers and may have shiny crystals, formed by minerals growing slowly over time, on their surface. Examples of this rock type include granite and marble. These types of rocks break down slowly, forming cliffs along coastlines, plateaus within continents and last long epungh for thick layers of dirt to from creating rich areas of forest and plains.
Igneous
Igneous rocks are formed when magma (molten rock deep within the earth) cools and hardens. Sometimes the magma cools inside the earth, and other times it erupts onto the surface from volcanoes. Examples of this rock type include basalt and obsidian. These type of rocks are often very new and have not had a huge amount of time to from deep layers of loamy earth needed for grasslands or forests but often contain crystals and gemstones! Bare rock itself is also quite common!
If you want to take advantage of having rock types in your map another overlay with a pattern works really well, using our previous little map you can see how I made things work, any random pattern will work here though!
Rivers
Unlike the previous subjects, rivers and how people use them in fantasy maps is a somewhat contentious subject. This is because rivers have hard rules that govern how they form and how they flow, you can't really mess with them in the same way. Getting it wrong can feel irritating to some because those rules need a reason for being broken and are as far as I know these rules are not broken in the real world.
Rivers start a higher altitudes and flow down into oceans, this means mountains! This is something we touched upon before but if a mountain is facing an ocean, that side will have rivers. But a few smaller rivers might reach the other side as well. They do not end in lakes, if your river goes into a lake it simply carries on again somewhere else until it hits an ocean. (Unless it's a stagnating inland sea)
One of the biggest rules regarding rivers, they never split. Water will always find the easiest path to the oceans. Finally fast parts of rivers run straight, slow parts curve and meader. Rivers are therefore straighter near mountains and hills and slower around plains and flat areas.
In the picture below (Terrible quality but its gets the point across) you can see the amazon river in South America. Flowing from the Andes mountains in the west all the way to the ocean. None of the smaller rivers that join the amazon split.
Here's our final little supercontinent map, nice and simple with some biomes, ocean currents and rivers that gives you a pretty clear idea about where to go next and how you might want to add more detail. You also have a clear understanding why these things are in those places which gives the map a more solid background to build upon in the future!
Simple Rules
All the rules and things I have talked about are very basic, you can add them to your map to help you if you are stuck but like anything in a fantasy setting you can ignore and change these rules to suit whatever kind of map you want to make. Magic is often used to explain why a map feature breaks these rules and although its cliché, it does work and can make your map stand out!
A famous example of this is the lonely mountain in Middle Earth.
It doesn't make sense for a mountain to sit on its own in the middle of a continent.
Mountains are typically created and formed in ranges due to tectonic plates but the lonely mountain is a great visual feature that is central to the plot of the Lord of the Rings. In short it's cool. Therefore breaking the rules in a world full of elves, dwarves and dragons is absolutely fine!
Final Thoughts
I have missed out on a huge amount of detail in this article and you can look up and study each of these points and aspects of geography for hours. For fantasy mapmaking though, this should give you a great starting point! Come and chat with me on twitter or my discord about any of these subjects or with help on creating your own temperature maps, rock maps or tectonic plate maps, I will gladly offer suggestions and advice!
I’m going to do some more little mapmaking articles in the future as well so if you have any ideas please let me know!
As always, thanks for reading!