San Francisco’s local rail system is a unique hybrid of a legacy streetcar network (consisting of five lines that survived the busstitution era only because they used tunnels or off-street rights-of-way), a downtown subway (which connects to an old tunnel under the city’s central hills to provide an underground ride almost across the peninsula), and a modern light rail line that is currently being extended into downtown via its own subway. Its vehicles are modern, but because much of the system is on city streets, most trains are limited to two cars, resulting in Tokyo-level overcrowding. Boarding the old surface lines often requires walking out into the street and climbing up into the train; downtown, though, massive, three-level stations are shared with BART. The current version of the official Muni Metro map, meanwhile, is competent enough, but has one fatal flaw: it shows the major transfer point of Church and Duboce as two stops that appear to be a mile or more apart, suggesting riders must go all the way downtown, to Van Ness, to transfer between the J and N. It distorts downtown geography in a confusing way, sending trains east from Embarcadero rather than south and having them turn right, not left at Fourth and King. Finally, it wasn’t “future-proofed” to accommodate the under-construction Central Subway. Like the existing map, this diagram could come in black or white versions.