Caldecott Medal-winning author and illustrator David Macaulay takes readers on a visual journey through a city's various support systems--the many tunnels, pipes, walls, and other structures that help sustain the bustling life above. In Underground, Macaulay exposes a typical section of this intricate underground network and explains how it works.

Along with his beautiful illustrations, Macaulay presents "a straightforward yet fascinating description of the labyrinth beneath the feet of any city dweller. And what a complex covered world [he] reveals! He invents an intersection of two streets and proceeds to show what we all might find if we dared to descend through that Alice-in-Wonderland manhole" (The New York Times).