There were two means - coastal ships and a post-horse courier system in land areas.
A system of sea, river and road transport.
Sea transport and a system of tracks with way stations for mounted couriers.
Ships around the coast and in the rivers, seas and lakes, and a horse-relay courier system by land.
Well-maintained roads and way statuons that provided food, shelter, and fresh horses for the kings messengers!
In the absence to today's methods of communication, it established a system of roads with posting houses along the way which provided horses and messengers to pass information rapidly. It also used sea transport transmission to areas with water access.
Ships in the coastal areas, and courier tracks in the inland areas.
A fleet, and internal roads with posting houses for horsed couriers.
It's systematic use of sea and river craft and posting road horse couriers.
A fleet of ships was the most efficient. For those areas not accessible by water, there was a horsed courier system with way stations with fresh mounts to speed progress.
One was the introduction of Aramaic as the common language of the Empire, which facilitated communication between the varied peoples of the Empire. Jesus of Nazareth over 500 years later would have spoken his message in Aramaic. The Persians also built a system of roads which, in conjunction with sea transport, provided physical communication for contact and trade.
The royal road system was developed primarily to enhance communication and trade across the vast Persian Empire. It facilitated the efficient movement of troops, officials, and goods, thereby strengthening central control and administration. Additionally, it improved the overall economic integration of diverse regions within the empire, allowing for quicker responses to challenges and fostering cultural exchange. This network was crucial for maintaining the power and influence of the Persian rulers.
The Royal Road in Persia, established by Darius I around 500 BCE, was a crucial infrastructure for military operations. It facilitated rapid troop movement and communication across the vast Persian Empire, allowing for swift responses to threats and efficient deployment of forces. The road also enabled the transportation of supplies and reinforcements, enhancing the empire's military effectiveness. Overall, the Royal Road was integral in maintaining the stability and control of the Persian Empire through military logistics.