Nerve Center

Its call sign is ATL and it manages 2,700 take offs and landings everyday. An army of airport staff oversee a quarter of a million people who pass through its gates, as well as their luggage and their safety. There are more planes in the air and on the ground Friday evening when the world's busiest airport is strained to capacity. The only way to handle it is to keep a cool head.

Grand Central Terminal moves 130,000 passengers a day over 400 miles of track and through 110 stations spread across New York City and upstate New York. It's one of the busiest train stations in the world with more than 700,000 people who use the terminal and every weekday morning at 08:40 - rush hour is at its peak.

It is one of the most important canals in the world - allowing over 13,000 vessels a year to take an 8-hour short cut across a continental divide - shaving 8,000 kilometers and up to 2 weeks off the alternate route around the tip of South America. With mere inches as the margin for error, ship captains must surrender control of their vessel to specially trained Canal pilots.

Since its inaugural performance, Cirque Du Soleil's "O" has enthralled over 10 million spectators. While the production on-stage is breath-taking, the real amazing feat of coordination happens behind the scenes. While 85 artists risk their lives performing over a 1.5 million-gallon pool, 145 technicians work tirelessly to ensure that everyone is safe through the final death-defying act.

They get more than 160,000 calls a year, an average of 438 a day. Washington DC's FEMS is one of the busiest all-hazards agencies in the US. When they're not putting out fires, rescuing people from collapsing buildings or determining the contents of a suspicious package left on the steps of the White House, they protect the district during special events at the nations' capitol.

Spread across 4300 acres of land, and 3200 acres of water and boasting 9 container terminals, the Port of Los Angeles - known affectionately as "America's Port"- is the biggest, busiest and most significant gateway to the North American market. With 500 million dollars worth of cargo passing through the LA wharves everyday, a delay at this port sends a ripple effect through the U.S. economy.