I recently fell down a very deep monochrome-shaped rabbit hole during my search for a cartographic style for this website. Part of that rabbit hole fascinated me immensely — hachure maps.
The short description of hachures is that they are a method of displaying relief on a map using nothing but lines of varying thickness. They've been around for a long time and are a great way to represent detail on terrain, especially in an era when printing technology was limited.
This tutorial is the result of a couple days of experimentation in QGIS on how to replicate the hachure style using geometry generators and other new features inside the latest QGIS 3.20 release.
I've tried to keep things as simple as possible, though I've also gone into as much detail as possible. It's worth mentioning that I've diverged from the traditional definition of hachures, though this approach is similar enough to fit the term.
I'd like to thank Benjamin Becquet who helped point me in the right direction on Twitter when I first started asking about hachure styling in QGIS. Definitely check out his feed as he's also working on similar cartographic styles.