Roman Concrete: What Makes It Last 2,000 Years?

Added: 2026-05-27

[00:00:00]How Roman concrete survived every earthquake for centuries, but there was one problem. Roman concrete should have crumbled after a century, yet it lasted 2,000 years. They used pozzolanic ash to bind the mortar, but pozzolana alone could not explain its durability. Until 1981, when researchers discovered a second ingredient, seawater sand. They poured water on the sand, friction dropped by half. This secret turned out to be their super strength formula.

[00:00:27]Still standing after so long.