Persepolis was the ceremonial capital of the Achaemenid Empire. It is situated in the plains of Marvdasht, encircled by the southern Zagros mountains, Fars province of Iran. It is one of the key Iranian cultural heritage sites and a UNESCO World Heritage Site since 1979. The earliest remains of Persepolis date back to 515 BC. The city, acting as a major center for the empire, housed a palace complex and citadel designed to serve as the focal point for governance and ceremonial activities.