If you want to get from the Pacific Ocean to the Atlantic Ocean by ship, you don't have a lot of options.
You can go around the Cape Horn, the southern point of South America, which will take you a long time. Or you can go through the Panama Canal, which is a lot quicker if you're going from, say, Shanghai to New York.
Because of all the traffic going through that 110-foot wide canal, they are expanding it to double the capacity and allow larger ships through.
Meanwhile, Nicaragua wants to build its own canal. The government recently awarded a Chinese company a contract to do just that.
This segment aired on July 22, 2013.