Worldbuilding Wednesdays: Basic Mapmaking

Welcome to Worldbuilding Wednesdays!  Every Wednesday, we spend what is probably far too much time walking through our worldbuilding process.  In this week's post, we arrive at a spot most people start at:  the map.

What We Have So Far

The world is ten times Earth's diameter, ten times Earth's mass, 100 times Earth's surface area, but with gravity 1/10 Earth's.  Light is provided by the Lantern, a moon of sorts that orbits the planet.  Two other moons, one we've been calling "red" and the other "blue," also orbit the planet.  One "day" is a little less than two Earth-days long, and one "week" (the time it takes for all three satellites to align) is, thanks to the fact that the planet and the moons are moving in different directions, just a shade over 9 Earth-days long.

The world doesn't have true seasons, but thanks to a tendency for rain patterns to be extraordinarily long-lasting, there are remarkably regular weather patterns.  Fog rolls from the sea hundreds of kilometers inland multiple times per day, and near the equator, a continent-sized rainstorm moves about the planet at regular intervals.  It wasn't mentioned last time, but thanks to the relatively light winds closer to the planet's surface, that interval is about 4 Earth months in length, which can serve as a local year.  With that, a year would consist of 16 local weeks: 12 relatively dry weeks, followed by a month of near-constant rain due to what we called "The Blanket."

Beyond this, the weather is going to be dictated by latitude and the shape of the landmasses of this world, which leads us to this week:  It's time to think about making a map.

Mapmaking for Dummies

It is absurdly easy to go into the weeds on mapmaking.  Hundreds of books have been written on the subject, there are dozens of computer programs devoted specifically to mapmaking, and there are quite a few games that have rules just for making maps.  Because we try to keep these posts to a readable length, we're going to skip past that and focus on a few good rules of thumb that go well with what we already have worked out.

  Making a Map From Scratch?  Think About Oranges.  If you have a tectonically active planet, that means that the outside surface will consist of a series of tectonic plates, all moving about on top of a "liquid" mantle of magma.

Want to know a really easy way to draw a map?  Figure out where the plates meet, and plant a mountain range there.  Find places where the plates are pulling away, and you've likely found yourself the bottom of an ocean.  And, if you want a good way to semi-randomly figure out where the plates are and how they're shaped, grab an orange.

No, we're not hungry.  We're going somewhere with this.

Peel the orange.  Keep all the peeled parts.  On the largest parts, draw an arrow or two.  Then, put the peel back on the orange.  Unless you're one of those weirdos who can peel an orange perfectly, you'll end up with a vaguely spherical object with a series of peel chunks that don't quite fit perfectly.  Several arrows indicate the direction the larger parts are trying to move.  Sometimes they'll be moving away from each other, others moving together.

If you want a map of the tectonic plates of your world, just sketch out your poorly-fitted peels.  As mentioned, you can put the major mountain ranges of your world in the spots where the plates are pushing together, and center the major oceans where they're pulling away.

  Making a Map From Scratch is For Suckers.  The most popular and enduring maps from fantasy are almost never drawn from scratch.  Isn't that neat?

Seriously.  Tolkien's Middle Earth was inspired by Western Europe.  Gygax based his original campaigns on a map of the U.S. that he held sideways.  The Forgotten Realms that serve as the main setting for modern Dungeons and Dragons looks suspiciously like the Pacific Northwest.  So on and so forth.  We aren't kidding:  the most enduring maps are those that take inspiration from real-world maps.

You may note that the map we use as a header for the Worldbuilding Wednesdays posts looks kind of familiar.  That would be because we were inspired by a strange but true fact:  if you were to take the Mediterranean Sea and plant it in Australia, it would fit inside the continent's borders almost perfectly.  A couple of mapmakers took this seriously and made some high-quality maps of what that would look like.  We, in turn, saw that and thought to ourselves, what if we made a similar map, but both Australia and the Mediterranean were rotated so that the "Strait of Gibraltar" opened out to the north, near what was once the westernmost point of Australia?  And then we stretched it across our world?

That header is the result.

  Only Make the Maps You Need, But Let Them Be Influenced By the Maps You Don't Need.  For ease of reference, we're going to say that our header map is a map of one continent on our world.  We aren't going to bother with drawing maps of the other continents, mostly because, for purposes of our worldbuilding, we won't be developing those other continents.

That isn't to say that we shouldn't consider those continents, though.  For example, let's say that we want the ratio of land masses to ocean on our planet as exists on Earth.  Let's further say that the land masses are all roughly the same size.  Finally, let's pick a random number between 1 and 10 for the number of land masses; using random.org, we came up with 4.  That means there are four major continents, and combined they add up to about 100 times the land area of Earth.  Our twisted, flooded, stretched Australia, in turn, represents a land area 25 times Earth's.

Because of a random fact, a twisted map, and considering the continents we won't be using, we now have a fairly original map, without much fuss.

The Hilltop

The view from the Hilltop hasn't changed drastically.  Mostly what has changed is that we've got an idea of where, exactly, we're sitting.  In the distance, the coast curves, creating The Strait.  On Earth, the Strait would have been 13 kilometers wide, and the opposite side of the continent would have been visible.  Here, The Strait is 130 kilometers wide, and some of the roughest tides of the continent are flowing through here, as the Inland Sea pours into the Great Ocean.

These names, by the way, are all placeholders, just as we refer to the moons as the "red" moon and "blue" moon.  We'll discuss names later on, but it helps to have some basic labels when describing things.

Conclusion

Now that we've got some geography to work with and we know what the general climate is like, we'll be able to get specific about the geographic areas on our continent.  For example, we'll be able to identify the areas that will actually have snow, the regions that will be desert or forest, and the variety of climate zones in between.

Of course, we'll also need to figure out what each of those climate zones looks like.  It might be time to start considering actual life.

That's for next week.  Until then, happy worldbuilding!