City Wall of Stone & Opus Caementicium, Roman Empuries
A section of the Roman city-wall of Empuries, Spain. 1st century BCE. The base of the wall was made using calcareous rock while the upper portion is of Roman concrete (opus caementicium).
About the Author
Mark's special interests include ancient ceramics, architecture, and mythology. He loves visiting and reading about historic sites and transforming that experience into free articles accessible to all.