<Tr> <Td> </Td> <Td> This article needs additional citations for verification . Please help improve this article by adding citations to reliable sources . Unsourced material may be challenged and removed . (November 2016) (Learn how and when to remove this template message) </Td> </Tr> <P> The Persian Empire (Persian: شاهنشاهی ایران ‎, translit . Šâhanšâhiye Irân, lit .' Imperial Iran') refers to any of a series of imperial dynasties that were centred in Persia / Iran from the 6th century BC Achaemenid Empire era to the 20th century AD in the Qajar dynasty era . </P> <P> The first dynasty of the Persian Empire was created by Achaemenids, established by Cyrus the Great in 550 BC with the conquest of Median, Lydian and Babylonian empires . It covered much of the Ancient world when it was conquered by Alexander the Great . Persepolis is the most famous historical site related to Persian Empire in the Achaemenid era and it has been a UNESCO World Heritage Site since 1979 . </P> <P> From 247 BC to 224 AD, Persia was ruled by the Parthian Empire, which supplanted the Hellenistic Seleucid Empire, and then by the Sassanian Empire, which ruled up until the mid-7th century . </P>

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