From Explorica:
“Ingenious military engineering allowed the Allied forces to land at Arromanches on D-Day. Barges towed 600,000 tons of concrete across the English Channel, sinking them to create an artificial harbor, and then 33 jetties and 10 miles of floating roadways allowed the troops to land in France. Learn about this feat and other at the Arromanches Museum, where dioramas, interactive displays, and models detail the Allied landing.”