The Eiffel Tower
A wrought-iron lattice tower 330 meters tall, built on the Champ de Mars in Paris for the 1889 Exposition Universelle celebrating the centennial of the French Revolution. Its three platform levels are accessible by elevator, and the structure's exposed iron lattice — originally considered an eyesore by Parisian intellectuals — was designed with structural efficiency, each member sized precisely to resist wind loading. The tower was intended to be dismantled after 20 years but was preserved as a radio transmission antenna.
The Eiffel Tower is the most visited paid monument in the world, having received over 300 million visitors since 1889, and the defining symbol of Paris and of France as a cultural identity. Its construction demonstrated the aesthetic potential of honest structural expression — that an exposed iron skeleton could be beautiful rather than merely functional — pioneering the aesthetic of engineering-as-architecture that defines the Centre Pompidou, the Pompidou Centre, and countless contemporary buildings. It was the tallest man-made structure in the world from its completion until the Chrysler Building in 1930.
Eiffel's tower was designed as a temporary exhibition structure but became permanent through its usefulness as a radio transmitter, which saved it from demolition in 1909. The Parisian artistic establishment — including Maupassant, Verlaine, and Garnier — signed a protest against its construction as "a gigantic black factory chimney." Its vindication established the precedent that engineering structure could be accepted as a legitimate aesthetic form.