The concrete dome of the Pantheon in Rome remains stable enough for visitors to walk beneath, and some Roman harbours have underwater concrete elements that have not been repaired for two millennia – even though they are in regions often shaken by earthquakes.
Whence this remarkable resilience of Roman concrete architecture? It’s all down to the chemistry.
We already know how it works and it doesn’t work for modern uses of concrete. Of course it’s good to know, but it’s been some years now that people keep talking about roman concrete as if it’s adamantium or something