The Panama Canal

The Panama Canal

The Panama Canal  is a 77.1-kilometre (48 mi) ship canal in Panama that connects the Atlantic Ocean (via the Caribbean Sea) to thePacific Ocean. The canal cuts across the Isthmus of Panama and is a key conduit for international maritime trade. There are locks at each end to lift ships up toGatun Lake, an artificial lake created to reduce the amount of excavation work required for the canal, 26 metres (85 ft) above sea level. The current locks are 33.5 metres (110 ft) wide. A third, wider lane of locks is currently under construction and is due to open in 2016.

France began work on the canal in 1881, but had to stop because of engineering problems and high mortality due to disease. The United States took over the project in 1904, and took a decade to complete the canal, which was officially opened on August 15, 1914. One of the largest and most difficult engineering projects ever undertaken, the Panama Canal shortcut greatly reduced the time for ships to travel between the Atlantic and Pacific Oceans, enabling them to avoid the lengthy, hazardous Cape Horn route around the southernmost tip of South America via the Drake Passage or Strait of Magellan. The shorter, faster, and safer route to the U.S. West Coast and to nations in and around the Pacific Ocean allowed those places to become more integrated with the world economy. It takes between 20 and 30 hours to traverse the canal. The Panama Canal had its 100-year anniversary on August 15, 2014.

During construction, ownership of the territory that is now the Panama Canal was first Colombian, then French, and then American. 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, the canal was taken over by the Panamanian government in 1999, and is now managed and operated by the Panama Canal Authority, a Panamanian government agency.

Annual traffic has risen from about 1,000 ships in 1914, when the canal opened, to 14,702 vessels in 2008, the latter measuring a total of 309.6 million Panama Canal/Universal Measurement System (PC/UMS) tons. By 2008, more than 815,000 vessels had passed through the canal; the largest ships that can transit the canal today are called Panamax.^[1] The American Society of Civil Engineers has named the Panama Canal one of the seven wonders of the modern world.

The Golden Gate Bridge

The Golden Gate Bridge

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate strait, the mile-wide, three-mile-long channel between San Francisco Bay and the Pacific Ocean. The structure links the U.S. city of San Francisco, on the northern tip of the San Francisco Peninsula, to Marin County, bridging both U.S. Route 101 and California State Route 1 across the strait. The bridge is one of the most internationally recognized symbols of San Francisco, California, and the United States. It has been declared one of the Wonders of the Modern World by the American Society of Civil Engineers.^[7]

The Frommers travel guide considers the Golden Gate Bridge "possibly the most beautiful, certainly the most photographed, bridge in the world".^[8] It opened in 1937 and had, until 1964, the longest suspension bridge main span in the world, at 4,200 feet (1,300 m).

The Delta Works

The Delta Works

The Delta Works is a series of construction projects in the southwest of the Netherlands to protect a large area of land around the Rhine-Meuse-Scheldt delta from the sea. The works consist of dams, sluices, locks, dykes, levees, and storm surge barriers. The aim of the dams, sluices, and storm surge barriers was to shorten the Dutch coastline, thus reducing the number of dikes that had to be raised.

Along with the Zuiderzee Works, Delta Works have been declared one of the Seven Wonders of the Modern World by the American Society of Civil Engineers.

The Empire State Building

              

The Empire State Building

                 

 The Empire State Building is a 103-story skyscraper located in Midtown Manhattan, New York City, at the intersection of Fifth Avenue and West 34th Street. It has a roof height of 1,250 feet (380 m), and with its antenna spire included, it stands a total of 1,454 feet (443 m) high.^[6] Its name is derived from the nickname for New York, theEmpire State. It stood as the world's tallest building for nearly 40 years, from its completion in early 1931 until the topping out of the original World Trade Center's North Tower in late 1970.^[12] Following the September 11 attacks in 2001, the Empire State Building was again the tallest building in New York (although it was no longer the tallest in the US or the world), until One World Trade Center reached a greater height on April 30, 2012.^[13] The Empire State Building is currently the fourth-tallest completed skyscraper in the United States (after the One World Trade Center, the Willis Tower and Trump International Hotel and Tower, both in Chicago), and the 23rd-tallest in the world (the tallest now is Burj Khalifa, located in Dubai). It is also the fifth-tallest freestanding structure in the Americas.

The Empire State Building is generally thought of as an American cultural icon. It is designed in the distinctive Art Deco style and has been named as one of the Seven Wonders of the Modern World by the American Society of Civil Engineers. The building and its street floor interior are designated landmarks of the New York City Landmarks Preservation Commission, and confirmed by the New York City Board of Estimate.^[14] It was designated as a National Historic Landmark in 1986.^[10][15][16] In 2007, it was ranked number one on the AIA's List of America's Favorite Architecture.

The building is owned by the Empire State Realty Trust, for which Anthony Malkin serves as Chairman, CEO and President.^[17] In 2010, the Empire State Building underwent a $550 million renovation, with $120 million spent to transform the building into a more energy efficient and eco-friendly structure.^[18] Receiving a goldLeadership in Energy and Environmental Design (LEED) rating in September 2011, the Empire State Building is the tallest LEED certified building in the United States.

The Itaipu Dam

The Itaipu Dam

The Itaipu Dam  Portuguese pronunciation: [itɐjˈpu], locally: [ita.iˈpu], Spanish pronunciation: [itaiˈpu]) is a hydroelectric damon the Paraná River located on the border between Brazil and Paraguay. The name "Itaipu" was taken from an isle that existed near the construction site. In the Guaraní language, Itaipu means "the sounding stone".

The dam is the largest operating hydroelectric facility in terms of annual energy generation, generating 98.3 TWh in 2012 and 98.6 TWh in 2013, while the annual energy generation of the Three Gorges Dam was 98.1 TWh in 2012 and 83.7 TWh in 2013.^[1] It is a binational undertaking run by Brazil and Paraguay at the Paraná River on the border section between the two countries, 15 km (9.3 mi) north of the Friendship Bridge. The project ranges from Foz do Iguaçu, in Brazil, and Ciudad del Este in Paraguay, in the south to Guaíra and Salto del Guairá in the north. The installed generation capacity of the plant is 14 GW, with 20 generating units providing 700 MW each with a hydraulic design head of 118 m. In 2013 the plant generated a record 98.6 TWh, supplying approximately 75% of the electricity consumed by Paraguay and 17% of that consumed by Brazil.^[1]

Of the twenty generator units currently installed, ten generate at 50 Hz for Paraguay and ten generate at 60 Hz for Brazil. Since the output capacity of the Paraguayan generators far exceeds the load in Paraguay, most of their production is exported directly to the Brazilian side, from where two 600 kV HVDC lines, each approximately 800 km long, carry the majority of the energy to the São Paulo/Rio de Janeiro region where the terminal equipment converts the power to 60 Hz.

CN Tower

CN Tower

                            The CN Toweris a 553.33 m-high (1,815.4 ft) concrete communications and observation tower in Downtown Toronto, Ontario, Canada.^[3][6] Built on the former Railway Lands, it was completed in 1976, becoming the world's tallest free-standing structure and world's tallest tower at the time. It held both records for 34 years until the completion of Burj Khalifa and Canton Tower in 2010. It remains the tallest free-standing structure in the Western Hemisphere, a signature icon of Toronto's skyline, and a symbol of Canada, attracting more than two million international visitors annually.^[5][9]

Its name "CN" originally referred to Canadian National, the railway company that built the tower. Following the railway's decision to divest non-core freight railway assets, prior to the company's privatization in 1995, it transferred the tower to the Canada Lands Company, a federal Crown corporation responsible for real estate development. Since the name CN Tower became common in daily usage, the abbreviation was eventually expanded to Canadian National Tower or Canada's National Tower. However, neither of these names is commonly used.^[10]

In 1995, the CN Tower was declared one of the modern Seven Wonders of the World by the American Society of Civil Engineers. It also belongs to the World Federation of Great Towers, where it holds second-place ranking.

Channel Tunnel

Channel Tunnel

             The Channel Tunnel (French: Le tunnel sous la Manche; also referred to as the Chunnel)^[2][3] is a 50.5-kilometre (31.4 mi) rail tunnel linking Folkestone, Kent, in the United Kingdom, with Coquelles, Pas-de-Calais, near Calais in northern France, beneath the English Channel at the Strait of Dover. At its lowest point, it is 75 m (250 ft) deep.^[4][5][6] At 37.9 kilometres (23.5 mi), the tunnel has the longest undersea portion of any tunnel in the world, although the Seikan Tunnel in Japan is both longer overall at 53.85 kilometres (33.46 mi) and deeper at 240 metres (790 ft) below sea level. The speed limit in the tunnel is 160 kilometres per hour (99 mph).^[7]

The tunnel carries high-speed Eurostar passenger trains, the Eurotunnel Shuttle for automobiles and other road vehicles—the largest^[8] such transport in the world—and international rail freight trains.^[9] The tunnel connects end-to-end with the LGV Nord and High Speed 1 high-speed railway lines.

Ideas for a cross-Channel fixed link appeared as early as 1802,^[10][11] but British political and press pressure over compromised national security stalled attempts to construct a tunnel.^[12] An early attempt at building a Channel Tunnel was made in the late 19th century, on the English side "in the hope of forcing the hand of the English Government".^[13] The eventual successful project, organised by Eurotunnel, began construction in 1988 and opened in 1994. At £4.650 billion, the project came in 80% over its predicted budget.^[14] Since its construction, the tunnel has faced several problems. Fires and cold weather have both disrupted operation of the tunnel.^[15][16]Illegal immigrants have attempted to use the tunnel to enter the UK,^[17] causing a minor diplomatic disagreement over the siting of the Sangatte refugee camp, which was eventually closed in 2002.