The construction of the canal was proposed by the engineer and French diplomat Ferdinand de Lesseps, who in 1854 acquired from Said Pasha the rights of constructing and operating the canal for a period of 99 years. The "Compagnie Universelle du Canal Maritime de Suez" was formed. Construction took 11 years, and the canal opened on 17 November 1869. The canal had an immediate and dramatic effect on world trade. In July 1956, just a few days after the fourth anniversary of the Egyptian Revolution of 1952, the Egyptian government under President Gamal Abdel Nasser nationalised the Suez Canal Company, which had been run by the French and owned privately, with the British as the largest shareholders. The Israeli–British–French invasion of Egypt which followed is known in Egypt as the Tripartite Aggression but elsewhere as the Suez Crisis. Following Israel's invasion and occupation of Egypt's Sinai Peninsula in the Six-Day War of 1967, the Canal was closed, and did not reopen until 1975. Today, the Canal is a vital link in world trade, and contributes significantly to the Egyptian economy; in 2009 the income generated from the canal accounted for 3.7% of Egypt's GDP. The Isthmus of Suez is considered the boundary between Africa and Asia. Köppen-Geiger climate classification system classifies its climate as a hot desert (BWh). The hottest recorded temperature was on June 14, 1965 while the coldest recorded temperature was on February 23, 2004. Suez is twinned with:     William Matthew Flinders Petrie, A History of Egypt. Volume 3: From the XIXth to the XXXth Dynasties, Adamant Media Corporation, , p. 366 Barbara Watterson (1997), The Egyptians, Blackwell Publishing, , p. 186