Why did the Romans use limestone to build their aqueducts?
Limestone or, to be more precise, reconstituted limestone is, perhaps, the oldest and technologically very advanced building material. Back nearly 5,000 years it was used by Ancient Egyptians to construct their pyramids (recent studies have shown that the pyramid bricks were made of limestone cement, and not cut as the longstanding belief assumed). The Romans simply took the existing technology and applied it to aqueducts, bridges and other constructions.
