Panama Canal Zone
The Panama Canal Zone () was an unincorporated territory of the United States from 1903 to 1979, centered on the Panama Canal and surrounded by the Republic of Panama. The zone consisted of the canal and an area generally extending on each side of the centerline, excluding Panama City and Colón, which otherwise would have been partly within the limits of the Zone. Its border spanned three of Panama's provinces. When reservoirs were created to assure a steady supply of water for the locks, those lakes were included within the Zone.
History of the Panama Canal
Theodore Roosevelt believed that a US-controlled canal across Central America was a vital strategic interest of the country. This idea gained wide circulation after the destruction of the USS "Maine" in Cuba on February 15, 1898. Reversing a Walker Commission decision in favor of a Nicaraguan canal, Roosevelt encouraged the acquisition of the French Panama Canal effort. George S. Morison was the only commission member who argued for the Panama location. The purchase of the French-held land for $40 million was authorized by the June 28, 1902 Spooner Act. Since Panama was then part of Colombia, Roosevelt began negotiating with that country to obtain the necessary rights. In early 1903 the Hay–Herrán Treaty was signed by both nations, but the Senate of Colombia failed to ratify the treaty.