The Panama Canal is a man-made canal in Panama which joins the Pacific and Atlantic oceans. One of the largest and most difficult engineering projects ever undertaken, it had an enormous impact on shipping between the two oceans, replacing the long and treacherous route via the Drake Passage and Cape Horn at the southernmost tip of South America. A ship sailing from New York to San Francisco via the canal travels 9,500 km (6,000 miles), well under half the 22,500 km (14,000 mi) route around Cape Horn. Although the concept of a canal near Panama dates back to the early 16th century, the first attempt to construct a canal began in 1880 under French leadership. After this attempt failed and saw 21,900 workers die, the project of building a canal was attempted and completed by the United States in the early 1900s, with the canal opening in 1914. The building of the 77 km (48 mi) canal was plagued by problems, including disease (particularly malaria and yellow fever) and landslides. By the time the canal was completed, a total of 27,500 workers are estimated to have died in the French and American efforts. Since opening, the canal has been enormously successful, and continues to be a key conduit for international naval trade. The canal can accommodate vessels from small private yachts up to large commercial vessels. The maximum size of vessel that can use the canal is known as Panamax; an increasing number of modern ships exceed this limit, and are known as post-Panamax vessels. A typical passage through the canal by a cargo ship takes around nine hours. 14,011 vessels passed through in 2005, with a total capacity of 278.8 million tons, making an average of almost 40 vessels per day.