Seventeenth of Tammuz
（重定向自Fast of Tammuz）
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The Seventeenth of Tammuz (Hebrew:שבעה עשר בתמוז, Shiv'ah Asar b'Tammuz) is a Jewish fast day commemorating the breach of the walls of Jerusalem before the destruction of the Second Temple. It falls on the 17th day of the Hebrew month of Tammuz and marks the beginning of the three-week mourning period leading up to Tisha B'Av.