The primary purpose of the ancient Roman aqueducts was to transport water from distant sources into cities and towns for public use. These structures were crucial for supplying water for drinking, bathing, and irrigation, thereby improving sanitation and public health. By engineering systems that utilized gravity to move water across valleys and hills, Romans could sustain urban populations and support large-scale agriculture. The aqueducts exemplified Roman engineering brilliance and played a vital role in the expansion of cities, contributing to the overall prosperity and development of the Roman Empire.