Panama_Canal_Zone

The Panama Canal Zone (Spanish: Zona del Canal de Panamá), also simply known as the Canal Zone, was a concession of the United States located in the Isthmus of Panama that existed from 1903 to 1979. It consisted of the Panama Canal and an area generally extending five miles (8 km) on each side of the centerline, but excluding Panama City and Colón. Its capital was Balboa.
The Panama Canal Zone was created on November 18, 1903 from the territory of Panama; established with the signing of the Hay–Bunau-Varilla Treaty, which allowed for the construction of the Panama Canal within the territory by the United States. The zone existed until October 1, 1979, when it was incorporated back into Panama.
In 1904, the Isthmian Canal Convention was proclaimed. In it, the Republic of Panama granted to the United States in perpetuity the use, occupation, and control of a zone of land and land underwater for the construction, maintenance, operation, sanitation, and protection of the canal. From 1903 to 1979, the territory was controlled by the United States, which had purchased the land from its private and public owners, built the canal and financed its construction. The Canal Zone was abolished in 1979, as a term of the Torrijos–Carter Treaties two years earlier; the canal itself was later under joint U.S.–Panamanian control until it was fully turned over to Panama in 1999.