Rules Index | GM Screen

GameMastery Guide / Creating a World / Geography / Terrain Hierarchy

Rivers

Source GameMastery Guide pg. 147
Once you have the elevations of your region marked, you’ll be able to place rivers. Start near the centerline of a mountain range and wind downward on whatever curving course you want as you approach a coastline. Make sure that your rivers don’t double back across an elevation line once they cross it, since water has a hard time flowing uphill. One important thing to keep in mind is that, as a general rule, water wants to flow together rather than apart—as a result, you should avoid having your rivers “split” as they flow downward from the mountains, save to create a delta like those at the mouths of the Mississippi or the Nile. Likewise, make sure that you don’t have multiple rivers emptying out of a lake!

Archives of Nethys

Rules Index | GM Screen

Rivers