<Table> <Tr> <Td> </Td> <Td> This article is incomplete . Please help to improve it, or discuss the issue on the talk page . (March 2017) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article is incomplete . Please help to improve it, or discuss the issue on the talk page . (March 2017) </Td> </Tr> <P> The Persian Empire (Persian: شاهنشاهی ایران, translit . Šâhanšâhiye Irân, lit .' Imperial Iran') is a series of imperial dynasties centered in Persia / Iran since the 6th century BC in Achaemenid era, to the 20th century AD in Qajar 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 Achaemenid era and it is a UNESCO World Heritage Site since 1979 . </P>

When did the persian empire begin and end
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