What’s the most surprising fact about architecture

I just graduated and I’ve been diving into as many architecture-related internships as I can to learn the ropes before getting licensed. I stumbled upon this crazy fact: the Pantheon in Rome has the world’s largest unreinforced concrete dome, and it’s been standing for nearly 2,000 years! It made me think about the incredible engineering challenges we face today. What other surprising trivia do you all know about iconic structures?

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