Mourning for the destruction of the Temples, from the breach of Jerusalem's walls to their fall. The Three Weeks or Bein ha-Metzarim (Hebrew: בין המצרים, lit. 'Between the Straits') is a period of mourning commemorating the destruction of the first and second Jewish Temples. The Three Weeks start on the seventeenth day of the Jewish month of Tammuz—the fast of the Seventeenth of Tammuz—and end on the ninth day of the Jewish month of Av—the fast of Tisha B'Av, which occurs exactly three weeks later. Both of these fasts commemorate events surrounding the destructions of the Temple in Jerusalem and the subsequent exile of the Jews from the land of Israel. According to conventional chronology, the siege of Jerusalem by Nebuchadnezzar II occurred in 586/7 BCE and the second siege of Jerusalem (70), by the Roman Empire, in 70 CE. Jewish chronology, however, traditionally places the first destruction at about 421 BCE: see missing years (Jewish calendar) for more information. Wiki link Dates: Hebcal.com (CC BY 4.0), Diaspora schedule. Text: Wikipedia (CC BY-SA).