About how far was the shortest distance from Greece to the western end of the royal road?

The shortest distance from Greece to the western end of the Royal Road, which was located in Sardis (in present-day Turkey), is approximately 1,000 kilometers (around 620 miles). This ancient road connected various regions of the Persian Empire, facilitating trade and communication. Its construction significantly impacted the movement of people and goods during its time, enhancing connectivity across the empire.