(Vertical) transportation and urban form:

Nick Paumgarten in the New Yorker:

In New York City, home to fifty-eight thousand elevators, there are eleven billion elevator trips a year—thirty million every day—and yet hardly more than two dozen passengers get banged up enough to seek medical attention. The Otis Elevator Company, the world’s oldest and biggest elevator manufacturer, claims that its products carry the equivalent of the world’s population every five days. As the world urbanizes—every year, in developing countries, sixty million people move into cities—the numbers will go up, and up and down.

Two things make tall buildings possible: the steel frame and the safety elevator. The elevator, underrated and overlooked, is to the city what paper is to reading and gunpowder is to war. Without the elevator, there would be no verticality, no density, and, without these, none of the urban advantages of energy efficiency, economic productivity, and cultural ferment. The population of the earth would ooze out over its surface, like an oil slick, and we would spend even more time stuck in traffic or on trains, traversing a vast carapace of concrete. And the elevator is energy-efficient—the counterweight does a great deal of the work, and the new systems these days regenerate electricity. The elevator is a hybrid, by design.