Completed on 1914, this 48 mile-long (77 km) international waterway known as the Panama Canal allows ships to pass between the Atlantic Ocean and Pacific Ocean, saving about 8000 miles (12,875 km) from a journey around the southern tip of South America, Cape Horn.
The existence of the canal makes a trip from the east coast to the west coast of the U.S. much shorter than the route taken around the tip of South America prior to 1914. Though traffic continues to increase through the canal, many oil supertankers and military battleships and aircraft carriers can not fit through the canal. There's even a class of ships known as "Panamax," those built to the maximum capacity of the Panama canal and its locks.
In September, 2007 work began on a $5.2 billion project to expand the Panama Canal. Expected to be complete in 2014, the Panama Canal expansion project will allow ships double the size of current Panamax to pass through the canal, dramatically increasing the amount of goods that can pass through the canal.