The Eiffel Tower is made of puddle iron, which is the precursor to construction steel. The tower is composed of 18,000 specifically designed and calculated pieces, each traced out to an accuracy of a tenth of a millimeter. The tower was assembled using wooden scaffolding and small steam cranes mounted onto the tower itself. The assembly of the first level was achieved by the use of hydraulic jacks. The construction work began in January 1887 and was finished on March 31, 1889. The tower is 330 meters tall, about the same height as an 81-storey building, and the tallest structure in Paris.

In summary, the Eiffel Tower is made of puddle iron and was assembled using wooden scaffolding and small steam cranes mounted onto the tower itself. The tower is composed of 18,000 specifically designed and calculated pieces, each traced out to an accuracy of a tenth of a millimeter. The construction work began in January 1887 and was finished on March 31, 1889. The tower is 330 meters tall, about the same height as an 81-storey building, and the tallest structure in Paris.