Every city has its drawbacks -- parking, for example, or crime, or the price of a decent pizza slice -- but in the 1800s London faced a particularly unusual and disgusting problem: the city literally stank. And this wasn't an occasional whiff of urine or hot garbage from an alleyway, oh no. Instead, a pervasive stench permeated the area, an odor so strong that it disrupted Parliament, forcing the government to take action (and eventually rewriting our understanding of disease in the process).