Engineering · Roman Empire Daily
Roman water pipes were made of lead, 'plumbum,' which is where the word 'plumbing' comes from.
Deep dive
Lead pipes (fistulae) carried water through cities, and a 'plumbarius' was a pipe-worker. Notably, Vitruvius warned that clay pipes gave healthier water than lead.
Source: Vitruvius, 'On Architecture,' 8.6.10–11.