Here in Boston, rather than cardinal directions, subways and commuter trains head “inbound” or “outbound”—and, as in many cities, it’s notably easier to go down a “spoke” to the hub than it is to travel between spokes.

Build railroads at the same time that you were building roads, and solving the metropolitan transportation problem would be greatly simplified. Pour all available funds into roads without building railroads, and that problem would never be solved.