The Eiffel Tower is a wrought iron lattice tower on the Champ de Mars in Paris, France. It is named after the engineer Gustave Eiffel, whose company designed and built the tower.
Constructed from 1887–89 as the entrance to the 1889 World's Fair, it was initially criticized by some of France's leading artists and intellectuals for its design, but it has become a global cultural icon of France and one of the most recognisable structures in the world. The Eiffel Tower is the most-visited paid monument in the world; 6.91 million people ascended it in 2015.
The tower is 324 metres (1,063 ft) tall, about the same height as an 81-storey building, and the tallest structure in Paris. Its base is square, measuring 125 metres (410 ft) on each side. During its construction, the Eiffel Tower surpassed the Washington Monument to become the tallest man-made structure in the world, a title it held for 41 years until the Chrysler Building in New York City was finished in 1930. Due to the addition of a broadcasting aerial at the top of the tower in 1957, it is now taller than the Chrysler Building by 5.2 metres (17 ft). Excluding transmitters, the Eiffel Tower is the second-tallest structure in France after the Millau Viaduct.
The tower has three levels for visitors, with restaurants on the first and second levels. The top level's upper platform is 276 m (906 ft) above the ground – the highest observation deck accessible to the public in the European Union. Tickets can be purchased to ascend by stairs or lift (elevator) to the first and second levels. The climb from ground level to the first level is over 300 steps, as is the climb from the first level to the second. Although there is a staircase to the top level, it is usually only accessible by lift.
The design of the Eiffel Tower was the product of Maurice Koechlin and Émile Nouguier, two senior engineers working for the Compagnie des Établissements Eiffel, after discussion about a suitable centrepiece for the proposed 1889 Exposition Universelle, a world's fair to celebrate the centennial of the French Revolution. Eiffel openly acknowledged that inspiration for a tower came from the Latting Observatory built in New York City in 1853. In May 1884, working at home, Koechlin made a sketch of their idea, described by him as "a great pylon, consisting of four lattice girders standing apart at the base and coming together at the top, joined together by metal trusses at regular intervals". Eiffel initially showed little enthusiasm, but he did approve further study, and the two engineers then asked Stephen Sauvestre, the head of company's architectural department, to contribute to the design. Sauvestre added decorative arches to the base of the tower, a glass pavilion to the first level, and other embellishments.
First drawing of the Eiffel Tower by Maurice Koechlin including size comparison with other Parisian landmarks such as Notre Dame de Paris, the Statue of Liberty and the Vendôme Column
The new version gained Eiffel's support: he bought the rights to the patent on the design which Koechlin, Nougier, and Sauvestre had taken out, and the design was exhibited at the Exhibition of Decorative Arts in the autumn of 1884 under the company name. On 30 March 1885, Eiffel presented his plans to the Société des Ingénieurs Civils; after discussing the technical problems and emphasising the practical uses of the tower, he finished his talk by saying the tower would symbolise,
Not only the art of the modern engineer, but also the century of Industry and Science in which we are living, and for which the way was prepared by the great scientific movement of the eighteenth century and by the Revolution of 1789, to which this monument will be built as an expression of France's gratitude.
Little progress was made until 1886, when Jules Grévy was re-elected as president of France and Édouard Lockroy was appointed as minister for trade. A budget for the exposition was passed and, on 1 May, Lockroy announced an alteration to the terms of the open competition being held for a centrepiece to the exposition, which effectively made the selection of Eiffel's design a foregone conclusion, as entries had to include a study for a 300 m (980 ft) four-sided metal tower on the Champ de Mars. On 12 May, a commission was set up to examine Eiffel's scheme and its rivals, which, a month later, decided that all the proposals except Eiffel's were either impractical or lacking in details.
After some debate about the exact location of the tower, a contract was signed on 8 January 1887. This was signed by Eiffel acting in his own capacity rather than as the representative of his company, and granted him 1.5 million francs toward the construction costs: less than a quarter of the estimated 6.5 million francs. Eiffel was to receive all income from the commercial exploitation of the tower during the exhibition and for the next 20 years. He later established a separate company to manage the tower, putting up half the necessary capital himself.
Work on the foundations started on 28 January 1887.
Those for the east and south legs were straightforward, with each leg
resting on four 2 m (6.6 ft) concrete slabs, one for each of the
principal girders of each leg. The west and north legs, being closer to
the river Seine, were more complicated: each slab needed two piles installed by using compressed-air caissons 15 m (49 ft) long and 6 m (20 ft) in diameter driven to a depth of 22 m (72 ft) to support the concrete slabs, which were 6 m (20 ft) thick. Each of these slabs supported a block of limestone with an inclined top to bear a supporting shoe for the ironwork.
Each shoe was anchored to the stonework by a pair of bolts 10 cm
(4 in) in diameter and 7.5 m (25 ft) long. The foundations were
completed on 30 June, and the erection of the ironwork began. The
visible work on-site was complemented by the enormous amount of exacting
preparatory work that took place behind the scenes: the drawing office
produced 1,700 general drawings and 3,629 detailed drawings of the
18,038 different parts needed.
The task of drawing the components was complicated by the complex
angles involved in the design and the degree of precision required: the
position of rivet holes was specified to within 0.1 mm (0.0039 in) and
angles worked out to one second of arc.
The finished components, some already riveted together into
sub-assemblies, arrived on horse-drawn carts from a factory in the
nearby Parisian suburb of Levallois-Perret
and were first bolted together, with the bolts being replaced with
rivets as construction progressed. No drilling or shaping was done on
site: if any part did not fit, it was sent back to the factory for
alteration. In all, 18,038 pieces were joined together using 2.5 million
rivets.
At first the legs were constructed as cantilevers, but about halfway to the first level, construction was paused in order to create a substantial timber scaffold.
This renewed concerns about the structural integrity of the tower, and
sensational headlines such as "Eiffel Suicide!" and "Gustave Eiffel Has
Gone Mad: He Has Been Confined in an Asylum" appeared in the tabloid
press. At this stage, a small "creeper" crane
designed to move up the tower was installed in each leg. They made use
of the guides for the lifts which were to be fitted in the four legs.
The critical stage of joining the legs at the first level was completed
by the end of March 1888.
Although the metalwork had been prepared with the utmost attention to
detail, provision had been made to carry out small adjustments in order
to precisely align the legs; hydraulic jacks
were fitted to the shoes at the base of each leg, capable of exerting a
force of 800 tonnes, and the legs were intentionally constructed at a
slightly steeper angle than necessary, being supported by sandboxes on the scaffold. Although construction involved 300 on-site employees, only one person died thanks to Eiffel's stringent safety precautions and the use of movable gangways, guardrails and screens.
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| The start of the erection of the metalwork. |
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| 7 December 1887: Construction of the legs with scaffolding. |
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| 20 March 1888: Completion of the first level. |
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| 15 May 1888: Start of construction on the second stage. |
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| 21 August 1888: Completion of the second level. |
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| 26 December 1888: Construction of the upper stage. |
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| 15 March 1889: Construction of the cupola. |
