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.
Postage stamps and postal history of the Canal Zone
The Republic of Panama was formally part of Colombia, and after it broke away from Colombia, with assistance from the United States, it established itself as a separate nation where it immediately became necessary to establish its own post offices and issue its own postage stamps. The Canal Zone Post Office was inaugurated on June 25, 1904. Beforehand the domestic rates of postage in the United States were made applicable to all possessions of the United States on June 20, 1904, which henceforth included the Canal Zone.