The tower looks solid and rigid, but it is actually a flexible, moving structure. Since iron reacts to heat, the summer sun hitting the exposed side of the metal causes it to expand. This thermal expansion can cause the summit to tilt away from the sun by up to six inches.
Wind also affects the structure, but Gustave Eiffel mastered aerodynamics to keep it safe. The open-lattice design allows strong winds to pass right through the gaps, which keeps the tower stable even during major storms.
Most visitors buy Eiffel Tower tickets strictly for the view, but the real marvel is the physics holding it up. Next time you visit, look closely at the rivets and curves to see how it works. Our guides on an Eiffel tour explain the math that has kept the Iron Lady standing tall for over 130 years.
