Where does the phrase, hell on wheels, come from?

Hell on Wheels

Primarily it's used today to mean a really reckless driver. But the origin goes back to the days of the wild West and has nothing to do with cars. When the transcontinental railroad got started, there was a lot of open land between towns. Opportunists after the money of those laboring on working on the railroad in these open spaces, simply rented flatcars and turned them into mobile brothels and gambling casinos. Religious zealots considered such activities the work of the devil and anyone who participated doomed for hell. So, these flatcars with prostitutes, gambling, drinking etc. were called hell on wheels. Other meanings today can be as a compliment that someone is very energetic, a real go-getter, or just very fast-moving.

from driving in Cairo on peak hour?

hell on wheels (Slang): extremely demanding, fast-paced, aggressive, effective, or the like: "The new job is hell on wheels. Our sales staff is hell on wheels when it comes to getting the most out of every account."

http://dictionary.reference.com/search?q=hell+on+wheels&r=66

The phrase "Hell on Wheels" was originally used to describe the itinerant collection of flimsily assembled gambling houses, dance halls, saloons, and brothels that followed the army of Union Pacific railroad workers westward as they constructed the American transcontinental railroad in the 1860s. The followers were called "hangers-on" according to Samuel Bowles.

The huge numbers of wage-earning young men working in what was a remote wilderness, far from the constraints of home, proved to be a lucrative opportunity for those with expertise at separating such men from their money.

One early documentation of the term "Hell on Wheels" being used to describe the phenomenon was by Springfield, Massachusetts Republican newspaper editor Samuel Bowles.

The phenomenon is documented as far east as North Platte, Nebraska. As the end of the line continually moved westward, Hell on Wheels followed along, reconstructing itself on the outskirts of each town that became in turn the center of activity for the Union Pacific's construction work.

All manner of criminal activity was rampant in Hell on Wheels, with murders occurring on an almost nightly basis. Frequently, the more respectable element of a town temporarily hosting Hell on Wheels became fed up with the crime and organized to combat it. For example, in Laramie, Wyoming, a conflict between town vigilantes and a Hell on Wheels criminal gang culminated in a protracted street battle.

http://en.wikipedia.org/wiki/Hell_on_Wheels