Δαρείο Α' (Darius I) was a prominent king of the Achaemenid Empire, ruling from 522 to 486 BCE. He is known for his administrative genius, which helped to expand and consolidate the empire, making it one of the largest in history. Darius implemented a system of provinces, called satrapies, each governed by a satrap to ensure efficient management and control. Darius is also famous for his construction projects, including the grand city of Persepolis, which served as the ceremonial capital of the empire. He promoted trade and communication by building the Royal Road, facilitating travel and commerce across vast distances.