Seventeenth of Tammuz

Seventeenth of Tammuz, the seventeenth day on the Hebrew calendar month of Tammuz, is a half-day (dawn to dusk) fast in Judaism, mourning the break-through of the final protective walls of ancient Jerusalem by Rome, leading to the destruction of the Second Temple and the ruin of Jerusalem and defeat for the Jews of Judea.

It is preceded by the fast of Tenth of Tevet seven months earlier, and it comes three weeks before the major 24 hour fast of the Ninth of Av.

The three weeks between the Seventeenth of Tamuz and the Ninth of Av are in themselves known as the Jewish holidays |- |align=center| Shabbat | Rosh Hashanah | Fast of Gedalia | Yom Kippur | Sukkot, Hoshanah rabbah and Shmini Atzeret | Simchat Torah | Chanukah | Tenth of Tevet | Tu B'shevat | Fast of Esther and Purim | Passover | Lag B'Omer | Shavuot | 17th of Tammuz | Tisha B'Av | Tu B'Av |- |align=center|National holidays of Israel |- |align=center| Yom HaShoah | Yom HaZikaron | Yom Ha'atzma'ut | Yom Yerushalayim |}