Although civilisations like those of Egypt and China are said to have been amongst the first to use postal services, and the Neo-Assyrian and Neo-Babylonian Empires in modern-day Iraq were using forms of mail delivery before the Persian Empire was founded in the 6th Century BC, the Persians of modern-day Iran took the idea of a postal system to previously unseen heights – and then some. They used an extensive network of roads worked by expert horsemen who covered stupefying distances throughout the massive, diverse empire with bewildering speed and unwavering resolve.
The Achaemenid Persians (approx. 550-330 BCE) were able to deliver, through the use of a system of couriers on horseback (known as pirradaziš in Old Persian), messages from one end of the massive Persian Empire to the other in a matter of days. According to scholars, a message could be sent from Susa, the administrative capital of the empire in western Iran, to Sardis, in what is now western Turkey, in between seven and nine days, following the Royal Road, a sort of highway connecting the two cities. In the Histories, the Greek historian Herodotus – who estimated that the approximately 2,600km distance would take three months on foot – marks Susa and Sardis as the extremities of the Royal Road, but the Persian postal system was far vaster.