I am currently reading about the Hellenic Roman/Greek era. There were some very smart people back then as well as a very advanced civilization. Many roads from the Roman Empire can still be found throughout Europe today.
Actually, it was the Romans who first used concrete (the Colliseum is built of it) and who introduced volcanic ash into the mix to make it tougher.
The Pantheon, which they built, was for many many years the largest unsupported domed building in the world. SPQR!
Regards,
