The Eiffel Tower grows 15 cm taller in summer
Some trivia is so bizarre it forces you to rethink your entire understanding of the world. Check out the fact below, see how others reacted, and scroll down to dive into the verified science and history behind it.
Metal expands when heated. The iron structure of the Eiffel Tower expands by about 15 centimetres (6 inches) during hot summer months as the iron heats and its atoms vibrate more, pushing further apart. This thermal expansion is why bridges have small gaps built in — engineers deliberately leave space for metal to expand and contract without warping. The Eiffel Tower's top can also lean up to 18 cm away from the sun on very hot days.
We think of iron as a fixed, rigid material. Discovering that a famous landmark is literally a different height depending on the season challenges that assumption.
The Science Behind It
Metal expands when heated. The iron structure of the Eiffel Tower expands by about 15 centimetres (6 inches) during hot summer months as the iron heats and its atoms vibrate more, pushing further apart. This thermal expansion is why bridges have small gaps built in — engineers deliberately leave space for metal to expand and contract without warping. The Eiffel Tower's top can also lean up to 18 cm away from the sun on very hot days.
Why Your Brain Finds This Hard to Believe
Sources & Verification
OddlyHuman Editors
VerifiedWritten and fact-checked by the OddlyHuman Behavioral Science Team. We verify all psychological, sociological, and historical claims against peer-reviewed journals, primary sources, and established encyclopedias to bring you accurate insights.
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