Photo: Tactile Muni Metro Map, San Francisco
Maps in underground stations on the Muni light rail network in San Francisco have raised route designation letters and route lines, as well as braille labels for station names. Nice!
I know that it’s entirely happenstance*, but I really appreciate the fact that the M, K, and T lines appear next to each other on the map, making an “MKT” for Market Street.
*Historical aside: Muni streetcar letters were originally assigned alphabetically in the order they came into being, all the way from A to N. Letters then disappeared as many of the old streetcar lines were converted to numerical bus routes, leaving us with the strange assortment of letters we have now. The modern T Line breaks from this naming convention, as it simply refers to the road it mostly runs along, Third Street.
"K" and "T" lines are probably so close together because they are one and the same. Only difference is that after Embarcadero the "K" line turns into the "T" and goes down 3rd St. I’m not sure how many trains only do the "K" route and the "T" route.