Mystery · Ancient Engineering
Rome's Concrete Sky
The dome of the Pantheon
The question
What is the giant dome of Rome's Pantheon, nearly 1,900 years old, made of?
- Solid marble blocks
- Bronze plates on a timber frame
- Concrete(correct answer)
The answer: Concrete
Emperor Hadrian completely rebuilt the Pantheon between about 118 and 128 CE as a circular building of concrete faced with brick, crowned by a great concrete dome about 43 metres across. Until modern times it was the largest dome ever built. The vast interior is lit only by the oculus, an 8-metre opening at the top of the dome.
- Civilization
- Ancient Rome
- Region
- Southern Europe
- Period
- Rebuilt c. 118–128 CE
- Location
- Rome, Italy
- Featured in
- Daily Discovery #007 · 8 November 2026
Image: Julian Lupyan, CC0, via Wikimedia Commons (cropped) (image source, opens in a new tab)
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