In its 150 years of operations, the Suez Canal has been through wars and high-stakes power struggles as it imposed itself as a vital international waterway. On the anniversary of its lavish opening ceremony on November 17, 1869, here is a look back at key dates in its history. As far back as the 19th century BC, a canal existed between the Red Sea and a section of the Nile River which links to the Mediterranean. Dug out during the reign of Pharaoh Sesostris III, it could only be navigated during the wet season and required regular dredging. It was eventually abandoned in the eighth century AD. From the 16th century, various plans were explored to build a navigable waterway between the Mediterranean and Red Sea, essentially providing a shortcut between Europe and Asia. In a breakthrough in 1854, French diplomat Ferdinand de Lesseps persuaded the new Egyptian ruler, Said Pasha, to grant him a concession to construct a canal from the Red Sea's Gulf of Suez to the Mediterranean. De Lesseps founded the Suez Canal Company in 1855 and the work was financed through the sale of shares, half of which were bought by the Egyptian ruler. Digging began in 1859, at first by labourers using picks and shovels, and later with steam- and coal-powered machinery. It involved about 60,000 workers. The canal was opened on November 17, 1869 in a grandiose ceremony at Port Said attended by European dignitaries including Napoleon III's wife, Empress Eugenie de Montijo. In November 1875 an indebted Said Pasha sold his shares to the British government, with French shareholders retaining the rest. Amid tussles for control, major powers signed in 1888 the Constantinople Convention that gave the waterway international status and open to all ships in times of war and peace. Egypt was not a signatory. The provision was not always respected, including during the two World Wars. On July 26, 1956 Egyptian President Gamal Abdel Nasser took the world by surprise by nationalising the canal to help finance construction of the Aswan Dam on the Nile. It sparked the Suez Crisis in which Britain, France and Israel – who feared the vital waterway could be cut off – colluded to attack Egypt. Israel invaded the Gaza Strip and Sinai Peninsula in October; two days later French and British air raids destroyed part of Egypt's air force. Nasser retaliated in November by sinking all 40 ships in the canal, which was closed until early 1957. As the tensions soared, Britain and then France ceded, and fighting abruptly ended after 10 days. The canal was reopened on March 29, 1957 under Egyptian control. Egypt closed it again in June 1967 during the Six-Day War when Israeli troops invaded Egypt's Sinai Peninsula and reached the east bank of the canal. It remained closed during the 1973 Yom Kippur War, when Egyptian forces crossed the canal in a bid to retake the Sinai. The Israeli army repelled the attack with a counter-crossing. The war ended with a UN-backed ceasefire. Talks resulted in a military disengagement deal in January 1974 that saw Israeli forces pull back from the canal, which returned to Egyptian control. After 15 months of demining work, it reopened to international shipping on June 5, 1975. On August 6, 2015 President Abdel Fattah El Sisi officially opened a new route along the canal after work in which part of the existing waterway was widened and deepened. The expansion is intended to cut the waiting times and double the number of ships using the canal to around 97 per day by 2023.