The Atomic Bombing of Hiroshima

Surviving a Pyroclastic Flow

civilext on Instagram: "How did Romans build stone walls in the middle of violent seas? Open water destroys modern concrete in decades—but Roman harbors have survived 2,000+ years of waves and storms. Their secret? A “magic” volcanic concrete that doesn’t weaken underwater—it gets stronger. Using wooden cofferdams and a rare mix of volcanic ash and seawater, Roman engineers created marine structures that self-heal over time. While today’s concrete often fails in 50 years, these ancient piers are