Sardis was the western terminus of the Persian Royal Road’s main imperial route. The road connected Sardis in Lydia with Susa in southwestern Iran and helped the Achaemenid administration move officials, messages, and supplies across the empire.
Herodotus described the route and its regular stations in the fifth century BCE. The road crossed much of Anatolia before continuing toward the Persian heartland. Its organized relay system allowed royal messages to travel far faster than ordinary travelers, using fresh horses and staffed stations along the way.
The Royal Road was not a single modern-style paved highway running unchanged across the empire. It was a maintained network of routes whose exact paths varied by region and period. Sardis had been the capital of the Lydian kingdom before Cyrus the Great conquered Lydia, and its continued importance made it a natural western base for Persian imperial administration.