Today I was digging through my D&D campaign archives and marveling at the detail I put into many of my maps and "historical accounts". A lot of these works I always did for my own amusement, to keep track of the long running timelines that my group would do. Young me had way more time and energy to record every event that happened in the Flanaess. From players' quest movements, to entire wartime troop movements, I wish I still had the ambition to put a tenth of this effort into my stalled Battles of Greyhawk series.
What I'm showing off today is a couple hand drawn maps of the Iuz-Furyondy region (using the Marklands-Iuz the Evil sourcebooks) from June 628 CY to Jan 629 CY. Yeah my timelines always ran well ahead of published canon so I worked in new info as it came out. The amazing thing is I can scarcely remember playing many of the events detailed on these maps. Map #1 has a line showing the path taken to rescue Riggby the cleric (from WG5 Mordenkainen's Fantastic Adventure), Chendl is under siege again, and evil is making gains in the Vesve Forest.
So there you have it. You can chronicle your player's exploits by use of timeline maps. While the subject is dry I hope some aspiring DM/mapmaker out there can find some inspiration from these scraps of notebook paper.