writing details directly on town maps, something occurred to me about old school maps. TSR-era maps are usually printed in a shade of blue, instead of in black. Specifically, it’s non-photo blue, RGB #A4DDED, a shade that can’t be detected by the graphics arts cameras typically used back then. TSR used this shade to prevent high-quality reproductions of their maps in bootleg copies of the modules.
This, of course, is no longer true with digital image techniques, but old schoolers are so used to seeing maps that look like that, there are a number of OSR publishers who do their maps in that color. For example, Dragonsfoot uses it in their modules. New schoolers laugh at the stupid nostalgia of the OSR.
However, when I made example maps GM info placement directly on town maps to reduce lookup time, I was having problems getting both the text and the underlying map to be equally readable. It was only after I posted my examples that I realized the solution is to print the player map in black, but make the GM map non-photo blue, so that that GMs can add notes directly to the map in pencil and still be able to read both the map and the notes. It’s a nice re-purposing of an old tradition.