What's up in the Big Apple? Well, how about three multi-billion construction projects - all underground - to expand what's already the nation's biggest mass transit system. Estimated completion time is 2019. Meantime, the good news is that more than a fair amount of ready mixed concrete is being placed through much of underground Manhattan.

"I look at it and I'm in wonder, I'm in awe," says engineer Michael Horodniceanu, president of capital construction for the state Metropolitan Transportation Authority. "I feel like when I went to Rome and entered St. Peter's Basilica for the first time. ... I looked at it and said, 'Wow, how did they do that?'"