Panama Canal

The Panama Canal (Spanish: Canal de Panamá) is a 77-kilometre (48 mi) ship canal in Panama that joins the Atlantic Ocean and the Pacific Ocean and is a key conduit for international maritime trade. Built from 1904 to 1914, annual traffic has risen from about 1,000 ships in the canal's early days to 14,702 vessels in 2008, measuring a total 309.6 milliontons. In total over 815,000 vessels have passed through the canal. It has been named one of the seven modern wonders of the world by the American Society of Civil Engineers.

Panama Canal in Days of Infamy
The Panama Canal was a high priority for the Japanese H8K's for reconnaissance. As the majority of US ship building docks were located on the east coast of the US mainland, they had to use the canal to move their carriers from the Atlantic to the Pacific.

However, the aggressive patrolling of the US in the Panama region made reconnaissance in that area impossible for the Japanese.