About 5,300 technical workshop drawings were produced for the Eiffel Tower.
The drawings were prepared by roughly 50 engineers and draftsmen working for Gustave Eiffel’s company. They detailed the tower’s thousands of iron components, allowing parts to be fabricated accurately in the company’s workshops at Levallois-Perret before being transported to the Champ de Mars for assembly.
This documentation was essential because the tower was effectively built as a giant prefabricated kit. Its 18,038 individual iron pieces had to meet at precise angles, with rivet holes positioned accurately enough for the parts to fit during assembly. The approach reduced the amount of cutting and shaping required on the construction site and helped the structure rise in just over two years.
Some detailed historical accounts give a larger total by separating 1,700 general drawings from 3,629 detailed drawings, or 5,329 altogether. The standard published figure for the project’s workshop drawings, however, is 5,300, making that the fair canonical answer to this trivia question. It should not be confused with the number of iron parts or the 2.5 million rivets used in the tower.