The construction lasted two years, two months and five days, and involved five hundred workers, who assembled eighteen thousand iron pieces, each of five meters and carefully numbered, which had been made at a factory in Levallois-Perret, a Paris suburb. Speaking of the tower construction workers, the son-in-law of Eiffel, declared, "no soldier on the battle field deserved better mention than these humble toilers, who, will never go down in history." During the Exposition, No one other than construction personnel were allowed higher than the second viewing platform.