As a railfan and a graphic designer, the first thing I check out when in a new town with public transit is their transit map. You can tell a lot about a city by how they represent themselves on a transit map, and I myself have designed more maps than I can count. What's the map of your city look like? Do you have a personal favourite you think is really unknown? Any maps that you just want to rant about because of how terrible it is?

My personal favourite transit map is Constantine Konovalov's Paris Metro Map, I just love how effortlessly it weaves the lines throughout the Peripherique, and how it's not afraid to break its own established rules on angles and circles. Honorable mentions go to the London Tube and Rail map (an absolute classic), and the Mexico City Metro, which assigns a unique symbol to every station for the benefit of passengers who can't read or write.

Also, designers, feel free to share your transit diagrams! I miss r/transitdiagrams a lot and would love to see your work, fictional, redesign or otherwise!