The Panama Canal Zone was a strip of land in Panama that was controlled by the United States from 1903 until 1979. It was established to facilitate the construction and operation of the Panama Canal, a significant waterway that connects the Atlantic Ocean to the Pacific Ocean. The canal greatly reduced travel time for ships, making it a crucial route for international trade. The zone covered approximately 553 square miles and included the canal itself, as well as surrounding areas. In 1977, the U.S. and Panama signed treaties to gradually transfer control of the zone back to Panama, which was completed on December 31, 1999.