Jewish History: Biblical History: The Period of the Second Temple:
How long did the Second Temple stand?
According to the Jewish tradition, it stood for 420 years (Talmud
Yoma 9a). This count of years is based on the computation in the
Seder Olam, according to which the Persian period, from Cyrus to
Alexander, was only 34 years long; see Talmud Avodah Zarah 9a.
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