The structure was built between 1887 and 1889 as the entrance arch for the Exposition Universelle, a World's Fair marking the centennial celebration of the French Revolution. Three hundred workers joined together 18,038 pieces of puddled iron (a very pure form of structural iron), using two and a half million rivets, in a structural design by Maurice Koechlin. Eiffel was assisted in the design by engineers Émile Nouguier and Maurice Koechlin and architect Stephen Sauvestre. The risk of accident was great as, unlike modern skyscrapers, the tower is an open frame without any intermediate floors except the two platforms. However, because Eiffel took safety precautions, including the use of movable stagings, guard-rails and screens, only one man died. The tower was inaugurated on 31 March 1889, and opened on 6 May.
The pig iron structure of the Eiffel Tower weighs 7,300 tonnes while the entire structure, including non-metal components, is approximately 10,000 tonnes. As a demonstration of the economy of design, if the 7,300 tonnes of the metal structure were melted down it would fill the 125 metre square base to a depth of only 6 cm (2.36 in), assuming the density of the metal to be 7.8 tonnes per cubic metre. Depending on the ambient temperature, the top of the tower may shift away from the sun by up to 18 cm (7.1 in) because of thermal expansion of the metal on the side facing the sun.
The tower has two restaurants: Altitude 95, on the first floor 311 ft (95 m) above sea level; and the Jules Verne, an expensive gastronomical restaurant on the second floor, with a private lift. This restaurant has one star in the Michelin Red Guide. In January 2007, the multi-Michelin star chef Alain Ducasse was brought in to run Jules Verne.
Since the beginning of the 20th century, the tower has been used for radio transmission. Until the 1950s, an occasionally modified set of antenna wires ran from the summit to anchors on the Avenue de Suffren and Champ de Mars. They were connected to long-wave transmitters in small bunkers; in 1909, a permanent underground radio centre was built near the south pillar and still exists today. On 20 November 1913, the Paris Observatory, using the Eiffel Tower as an antenna, exchanged sustained wireless signals with the United States Naval Observatory which used an antenna in Arlington, Virginia. The object of the transmissions was to measure the difference in longitude between Paris and Washington, D.C.Today, both radio and television stations broadcast their signals from the top of the Eiffel.
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| Eiffel Tower under construction in July 1888 |
Tallest in the world from 1889 to 1930
General information
Type : Observation tower,
Radio broadcasting tower
Location : Paris, France
Coordinates : 48.8583°N 2.2945°ECoordinates: 48.8583°N 2.2945°E
Construction started :1887
Completed :1889
Opening :31 March 1889
Height
Antenna spire :324.00 m (1,063 ft)
Roof :300.65 m (986 ft)
Top floor :273.00 m (896 ft)
Technical details
Floor count : 3
Elevator count : 9
Design and construction
Owner : France City of Paris, France (100%)
Management : Société d'Exploitation de la Tour Eiffel (SETE)
Main contractor : Gustave Eiffel & Cie
Architect : Stephen Sauvestre
Structural engineer : Maurice Koechlin,
Émile Nouguier
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