United States territorial acquisitions
The Panama Canal Zone was an unorganized US territory located within the Republic of Panama. It was established under the Hay–Bunau-Varilla Treaty in 1903 and disestablished in 1979 under the Torrijos–Carter Treaties. Panama gained full control over the Panama Canal in 1999.
Panama Canal Zone
The treaty was approved by the provisional Panamanian government on December 2, 1903, and by the US Senate on February 23, 1904. Under the treaty, Panama received , much of which the United States required to be invested in that country, plus annual payments of ; with those payments made, as well as for the purchase of the French company assets, the Canal Zone was formally turned over by Panama on May 4, 1904, when American officials reopened the Panama City offices of the canal company and raised the American flag. This marked the beginning point for U.S. excavation and construction which concluded in August 1914 with the opening of the canal to commercial traffic.