Manhattan Subway Project a Modern Marvel

Just another home addition for the Mole People....

..."one documentary estimated as many as 6,000-living illegally and dangerously in the subway tunnels."...

http://gawker.com/5956820/a-grisly-question-did-nycs-subway-dwelling-mole-people-get-out-alive

..."The city's annual tally indicated an additional 783 homeless people on the streets and in the subway system, for a total of 3,111, up from 2,328 last year. That is in addition to almost 38,000 people living in shelters, which is near the city's high.

The count came from an annual census of homeless people that is typically conducted on a cold January night, when more than 2,500 volunteers walk the streets and subway system between midnight and 4 a.m. to search for and identify the homeless. It took place this year on Jan. 25."...

http://www.nytimes.com/2010/03/20/nyregion/20homeless.html

Now if the history of underground railways really interests you, you should start here:-

First Underground Railway Opened 1863