Editing Mutant Underground PBP

In a panic over the Soviet Union successfully testing it's first atomic bomb in August of 1949, the U.S. authorized and funded a black project code named Tartarus. The project was to build the nation's first large scale nuclear fallout shelter, centrally located nationally, so that most important members of the federal government could be evacuated to the shelter in the case of a nuclear war.

Construction on the shelter began in the fall of that year, in the caverns beneath Chicago, which was deemed close enough to Washington DC for an evacuation, and to most of the rest of the nation to be considered "centrally located". 

The shelter, the first of it's kind ever attempted, was a colossal failure. There were problems with getting enough fresh air into the system, the engineers never got many of the seals working properly, which meant that fallout would never be able to be kept out of the shelter, and there were other problems as well.

Furthermore, with the advent of ICBM's, the national evacuation of the Federal Government to a centrally located bunker hundreds of miles from the capital became both impractical and foolish. The project was abandoned in 1958, and the lessons learned from the failed shelter were applied to the newer shelters being built in Washington DC and elsewhere.

The Tartarus shelter is the central hub of the Underground Railroad's community beneath the streets.