Workers completed tunneling for the first phase of the Second Avenue Subway on Sept. 22, 2011, when the project's tunnel boring machine reached the Lexington Av-63 St station, breaking into the ... more 
Workers completed tunneling for the first phase of the Second Avenue Subway on Sept. 22, 2011, when the project's tunnel boring machine reached the Lexington Av-63 St station, breaking into the existing subway system. The 485-ton, 450-foot-long TBM used a 22-foot diameter cutterhead to mine 7,789 linear feet in two tunnels, averaging approximately 60 linear feet a day. Photo by Metropolitan Transportation Authority / Patrick Cashin. less 
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Yahoo News | Photo By Metropolitan Transportation Authority / Patrick Cashin
Thu, Jun 13, 2013 5:00 PM EDT