Wikimedia
Wikipedia: The Hebrew, or Jewish, Calendar
An encyclopedia entry about the Jewish calendar with information on the history of the calendar as well as on the modern Jewish calendar, which dates from 3761 BCE. Names of the months, length of the months, leap years, and similar...
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Chabad Lubavitch: The Jewish Calendar
A storehouse of resources about the Jewish calendar from the educational wing of the Lubavitch Hasidim movement. Choose to view information about particluar holy days. View a current calendar page (by day, week, or month) to see events...