Undertown is a vast network of abandoned tunnels and sunken streets underneath the city of Chicago.
Undertown is a network of caves, ruined buildings, tunnels, and ancient construction underneath Chicago. It is a dark, damp, cold place full of creatures that shun sunlight and human company. It might be radioactive.
Dresden's Chicago used to be a swamp, level with Lake Michigan. It kept sinking and the City kept building and layering upwards. The lower levels exist as a whole city under the street level of the City proper. There used to be a problem with rats and criminals that got crowded out by supernatural things that do not take well to sunlight, creating a mini-civilization.
In the series
"Welcome to the Jungle"
In Death Masks, it is where the Denarians had set up shop. Nicodemus Archleone holds Harry Dresden captive under running cold water to nullify his magic. Nicodemus tries to recruit Dresden into the Denarians. Shiro trades himself for Dresden and then gives his Sword, Fidelacchius, into his keeping.
In "Down Town", Harry Dresden describes it to John Marcone as an area without any order or cohesion, where nothing appears as it is - doors open and close on their own, and tunnels' behavior is even trickier. Terror and despair dominate the area.
In "Something Borrowed", Georgia Borden is kidnapped by Jenny Greenteeth, put under a sleeping spell, and brought to Undertown, where she was guarded by shellycobbs. Dresden and Murphy are forced to fight them in order to rescue her.
- Manhattan Project - Wikipedia
- Google Maps - interactive picture of corner in daylight—arrows on bottom move your view around intersection, also clicking cursor on places, if get too close zoom out a little
- Randolph and Wabash - Flickr
- Randolph and Wabash II - Flickr
- Randolph and Wabash III - Flickr
- Manhattan Project - Encyclopedia Britannica
- The Manhattan Project - ushistory.org
- The Manhattan Project: Making the Atomic Bomb - atomicarchive.com