The Pantheon belongs to the Common Era — dated here to c. 126 CE at Rome, Italy. Dates mark a scholarly centre of gravity (dedication, completion, or iconic phase), not a single foundation day.
Hadrian’s temple keeps the largest unreinforced concrete dome ever built — an oculus that rains into the floor and still stands.
How it amazes the brain
Graded aggregate lightens the dome toward the top. Coffers reduce mass; the 43-metre span matches the height — a sphere inscribed in a cylinder.
Why it counts as a wonder
It never needed a contest ballot to scramble the brain: scale, craft, or sheer improbability is enough.
Michelangelo supposedly said it was angelic design. Modern engineers still reverse-engineer the mix.
On dating
CE means years after the traditional birth of Christ. A monument listed as c. 126 CE may have been founded earlier, rebuilt later, or become famous only in one phase. Engineering wonders (dams, tunnels, orbiting labs) are dated to opening or assembly.
This is story 2 of 100 in The Trend Ledger’s illustrated desk on world wonders raised after the birth of Christ — the companions to our BCE series.