Engineers in Roman society: Organising public building -- Aqueducts: Finding water -- Problems and solutions -- Supplies from the Anio -- Surveying the route -- Building the aqueduct -- Frontinus, Curator Aquarum -- Roads: Instruments of empire -- Setting out the route -- Structure of the Roman road -- High-quality surfaces -- Arteries of the Roman world -- Ports -- Bridges: Army's wooden bridges -- Stable stone arches -- Establishing foundations -- Erecting the stonework -- How the Romans adapted the arch -- Materials: Stone -- Mortar and concrete -- Bricks and tiles -- Metal and wood -- Roman achievement