Excavations near the Danube River in modern-day Bulgaria have revealed a massive Roman industrial hub dedicated to supplying the frontier legions. The site includes four specialized foundries for producing high-carbon steel weaponry and an extensive workshop for repairing Lorica Segmentata (plated armor), complete with thousands of discarded iron rivets and leather scrap.
Archaeologists also found a unique administrative archive consisting of inscribed lead tablets that record the quotas of swords and shields produced for the Danubian defense. This discovery highlights the immense logistical and industrial scale required to maintain the Roman Empire's borders during the 2nd century CE.