Yom HaZikaron / יום הזכרון

Israeli Memorial Day. Note that Hebcal displays modern holidays like Yom HaZikaron according to the Israeli schedule. Although Yom Hazikaron is normally observed on the 4th of Iyyar, it may be moved earlier or postponed if observance of the holiday (or Yom HaAtzma'ut, which always follows it) would conflict with Shabbat.
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List of Dates

Yom HaZikaron begins at sundown in the Diaspora on:

References

The Jewish Holidays: A Guide & Commentary
Rabbi Michael Strassfeld