Worldbuilding rivers: why are they so important?

Worldbuilding rivers often seems like an afterthought – just some squiggly lines on a map. But rivers are worldbuilding GOLD – from resources to defense to travel and industry, rivers provide some of the most important things your fictional cultures and fantasy races need. And they can provide fascinating conflicts for your stories too!

Why is worldbuilding rivers so important?

To create rivers that feel connected to the world, we first need to look at our world! So, here are five reasons rivers are so important for any civilization (with a few conflict ideas too!).

1. Rivers are a source of water

Well, duh, right? I know, it’s obvious! But that doesn’t mean it’s not important—we (as well as plants and animals) need water to survive. As it turns out, rain is usually not regular enough to keep an entire civilization running. Because we don’t just need water for drinking, we also have to take care of our crops and animals. And while rain might be enough for some kinds of crop, there’s a point where so much food is needed that rainwater might not be enough! I mean, just look at the first civilizations: Egypt appeared around the river Nile, and Mesopotamia between the rivers Tigris and Euphrates.

Actually, rivers were so important to these cultures that there are water and river deities in their religions, as well as religious festivals surrounding them! There are some interesting potential conflicts here, too. What happens if someone up river, in another country maybe, dams the water?

2. They are a quick way to travel

Before planes and fast cars were invented, a river was the quickest way to travel—provided that a navigable river connected with your destination, of course. And since most of the time they connect with the ocean, they’re a gateway to international travel for cities not located on the coast. For example, Rome wasn’t a coastal city during the Roman Empire. Instead, it was connected to the Mediterranean sea through the Tiber river, but being located inland defended it from sea raiders while still providing them with access to international travel.

Rivers are also a very practical way of transporting heavy objects or large quantities of trade goods. In Egypt, for instance, they used the Nile to transport the enormous blocks of stone needed to build the pyramids. Other common uses are lumber, ore and transporting industrial goods and resources. This ties in with the financial value rivers have!

And if a river is navigable, you can include two interesting conflicts. One is taxes. The Tower of London, for example, is situated so close to the river Thames for exactly that reason – it taxed river travel in and out of the city since it was built by the Normans in the 11th century. If your country controls a river that happens to be used as a travel route, it will probably want to tax any travellers that sail through its waters.

The other interesting travel-related conflict is RIVER PIRATES! They can add an interesting dimension to river travel in RPGs and novels, and it’s a great way to mix things up a bit!

Ancient Egyptians used rivers to transport stone blocks for the pyramids

You definitely can’t build one of those without an easy way to transport stone blocks!

3. Rivers act as natural borders

When two countries need to agree on a border, it’s much easier to take a natural border as a reference instead of manually building up a wall. So that’s what many countries have done throughout history—and rivers are examples of a natural border! For example, the Roman Empire used the Danube and the Rhine rivers as part of their borders. Modern countries do this all the time too, no need to look at ancient times! If you look at a map and see a squiggly line as a border, it’s probably a natural one. To see an example, look at the border between German and France: part of it is based on the Rhine river (which the Romans used too!).

An interesting conflict to consider here is: what happens when the river migrates? I know it sounds crazy, but this can happen over a long period, or very quickly! The Choluteca Bridge (in Honduras, pictured below) clearly illustrates an interesting real world example of quick river migration. Following Hurricane Mitch in 1998, the river shifted path so much that the bridge now sits BESIDE the river, rather than across it!

4. Rivers are defensive, and river crossings are tactical

If you’re building a defensive location, consider building by a river, particularly surrounded by one! A great real world example of this is the medieval city of Durham in the UK. It’s surrounded on three sides by a loop in the river, which makes it incredibly defensible. After all, it’s hard to attack someone across a river!

You can also flip this on its head, though. Since a river crossing is a place of extreme tactical importance (you know, if you’re moving an army and such), then having a fort that defends that river crossing can make or break a military campaign.

Stirling Castle in Scotland is a great example. It guarded the only viable crossing of the River Firth in the medieval period and into the 18th century. In fact, it was said that “he who holds Stirling, holds the North”. (Now you know what inspired G.R.R. Martin’s Winterfell Castle from Game of Thrones!)

5. Rivers provide resources, power and industry

And after all that, don’t forget that rivers provide resources too! Of course, there’s drinking water, fish, water fowl, reeds and other organic compounds. These are all very important if you like to eat and drink, and water your crops and make baskets and thatching.

But rivers are also sources of clay, sand and gravel, which are important for building and industry. And many rivers also provide easily accessible sources of tin, gold and platinum deposits, as wash down from deposits up stream.

And of course, from water wheels generating power to water-intensive activities like dying and tanneries, rivers are an excellent place to grow the industrial enterprises of your cultures and cities too. All these resources and energy are going to help your settlements and cultures not just survive, but thrive.

How to get started worldbuilding rivers

1. Geography is important!

It might seem obvious, but rivers always flow downhill! Sure, they meander around if the terrain is flat, but they’ll always choose the path of least resistance. This means that rivers almost never split into two without human intervention—why split if it can just take the shortest option of the two? Of course, if you’re worldbuilding fantasy, magic can mess everything up. You can even have uphill rivers, if that’s something your magic system can do!

When it’s time to put them on a map, don’t draw every single creek and steam, as you’d end up filling the entire map with water! Instead, draw the major rivers only, the ones that will define where countries and cities are placed. Small rivers don’t need to go to the world map: while you’re writing or playing, you can most likely add one in a plot-relevant location without issues (unless you’re in the middle of the desert)!

2. Think about civilizations when worldbuilding rivers

As explained above, there’s a lot of reasons to put your settlements near a river. That’s why major rivers are prime spots for the first civilizations of your world! Of course, civilizations rise and fall, so this doesn’t mean there will still be a powerful country in that place. But there will definitely be remnants of past civilizations! Think about city ruins, monuments, tombs, inscriptions, relics… This will immediately add more depth to your world’s ancient history, just by looking at the rivers!

If the civilization is still going strong, it will probably be a very powerful country—so think about their river control! If they don’t control the river source, they’ll probably want to either control it directly or have a powerful alliance with whoever does. And don’t forget about taxes: a big river means a lot of traffic, which means a lot of money flowing!

3. Use rivers to draw borders

Not all of them, obviously. But some borders should partially follow a river if you want to make them a bit more natural! A straight line means that the border was agreed upon on a treaty, while squiggly river borders are often the product of a country’s “natural” expansion (although it could be a treaty too). Think about how the river interacts with the countries—and how the countries interact with each other. Are they friendly? Are they sharing the river? The border could run through the middle of the river, or one nation could control the full river bed. What if they don’t agree? This has been a point of contention for many countries in the real world, so including these details in your world will make it feel more real!

The Rhine was used by the Romans as part of their borders!

4. Connect your rivers to the culture!

If the river has been important throughout the country’s history, people might have attached cultural significance to it! For example, they could see it as a god, or as the byproduct of one (a god’s tears, maybe?). If the entire civilization depends on that river, it might even be the head of the pantheon (if you have one) or if it’s in the border, it could be some sort of defender god. Think about how religion and festivals would develop around it and how they’ve influenced the daily life. If floods are common, maybe bowing when you cross the river is part of anyone’s daily life!

Whatever you decide to do, rivers have always been an extremely important part of our society. So they should feel important in your world building as well.