Panama Canal
Colombia, France, and later the United States controlled the territory surrounding the canal during construction. The US continued to control the canal and surrounding Panama Canal Zone until the 1977 Torrijos–Carter Treaties provided for handover to Panama. After a period of joint American–Panamanian control, in 1999, the canal was taken over by the Panamanian government. It is now managed and operated by the government-owned Panama Canal Authority.
Panama Canal
The United States initiated construction in 1850 of the Panama Railroad (now called the Panama Railway) to cross the isthmus and it opened in 1855. This overland link became a vital piece of Western Hemisphere infrastructure, greatly facilitating trade and largely determining the later canal route, which was made parallel to it.