[2]
Modern subway maps are far from geographically accurate, and the MBTA's is no exception (compare the spacing between Copley/Back Bay and Heath/Forest Hills). Peter Dunn wondered if he could come up with a true hub-and-spoke T map that provides a more useful metric for riders: The time it would take them to get from A to B [2]:
Riders need to know which line serves which station, and where to transfer to get there, but actual mileage or accurate compass directions aren't necessary to navigate the system. A time-scale map agrees, but adds a bit of information that the rider does care about: travel time. Stations are spaced according to travel time between them. (That's the average scheduled travel time; your results will vary.)