Q&A: How were large fleets supplied with food and water?

Where did the food and water for such large fleets come from?

These states already organized large supplies from fertile agricultural regions, irrigation systems, and established maritime networks.

Rome and Carthage already organized food and water supplies for large populations and armed forces. Fertile agricultural land and irrigation supported a surplus that could provision fleets. Carthage's maritime economy made the support of ships an established responsibility. Rome could devote a large share of its population and economic resources to prolonged war, so assumptions of ancient logistical incapacity can misrepresent the scale of its effort.