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.
Hay–Pauncefote Treaty
The Hay–Pauncefote Treaty is a treaty signed by the United States and Great Britain on 18 November 1901, as a legal preliminary to the U.S. building the Panama Canal. It nullified the Clayton–Bulwer Treaty of 1850 and gave the United States the right to create and control a canal across the Central American isthmus to connect the Pacific Ocean and the Atlantic Ocean. In the Clayton–Bulwer Treaty, both nations had renounced building such a canal under the sole control of one nation.