Danny takes us to New York City, where the largest public works project in the country is happening: a $15 billion expansion of the NYC transit system. He heads 150 feet underground to find out what can be done without shutting down the city above.

The London Aquatics Centre will host 44 swimming & diving events during the 2012 Olympics and live on as a new addition to the London landscape. Danny Forster goes with crews as they construct one of the most advanced swimming facilities ever built.

The $2 billion Mumbai Airport Expansion project is one of India's most ambitious undertakings ever. If they succeed, it could completely change the way airports are designed.