About ten years ago I made a heatmap of contra dances, which I've kept up to date. I recently had a request from someone who'd like to print out a copy for a poster, and while the one I built on the Google Maps API doesn't have a way to generate a high-resolution version it seemed like fun to make one from scratch:

This one includes both special events and regular dances. The code is on github. While I usually don't find AI tools very helpful in coding and don't bother, iterating on charts is a place where I find they do speed me up a lot.

I'm pretty happy with it, but let me know if you have tweaks to suggest!