Tunneling Below Second Avenue

Wikipedia - "Unlike ants, moles, gophers and skinks, humans aren’t instinctively tunneling creatures. When we go underground, we are partly admitting that we’ve made a mess on the surface and partly showing off. In Manhattan, where street traffic tends to stall, only one subway runs the length of the East Side. Every weekday, 1.3 million passengers — more than are carried in 24 hours by the transit systems of Boston, Chicago and San Francisco combined — cram onto the Lexington Avenue line. Yet the chaos above and below has inspired afeat: about 475 laborers are now removing 15 million cubic feet of rock and 6 million cubic feet of soil — more than half an Empire State Building by volume — out from under two miles of metropolis."
NYT: Tunneling Below Second Avenue
NYT: Way Down in the Hole
NYT: The Once and Future Dream of New York (Video)
W - Second Avenue Subway
IRT East Side Line
NYMag: The Long, Tortured History of the Second Avenue Subway