RELAY 5: ROADS

The First Networks

Roads represent humanity's first large-scale infrastructure networks. The Roman roads, the Silk Road, the Inca road system—these networks unified empires, enabled trade, and transmitted knowledge across vast distances. Road infrastructure required centralized planning, massive labor investment, and long-term maintenance.

Road infrastructure included not just the roads themselves, but also way stations, supply depots, military outposts, and communication systems. The ability to maintain roads determined the cohesion and power of empires. Roads that fell into disrepair signaled the decline of civilizations.

Roads enabled the movement of armies, goods, and ideas. Control of roads meant control of trade, military power, and cultural influence. The great empires were defined by their road networks.

Timeline: Approximately 2,500 to 1,500 years ago, with the development of major imperial road systems.

Impact: Enabled the creation of continental empires, facilitated long-distance trade, and unified diverse populations under single political systems. Road networks became the defining infrastructure of empires.

Legacy: Modern transportation networks—highways, railways, shipping lanes, air routes—are the direct descendants of ancient road systems. The principles of network design established by ancient roads continue to shape modern infrastructure.