Thousands of Israelis will fast on Monday night as they observe Tisha Be'av commemorating the destruction of the two Temples. Considered to be one of the saddest days on the Jewish calendar, worshippers will spend part of Monday night and Tuesday in solemn prayer as the Lamentations is recited. Places of entertainment such as cinemas and cafes and restaurants will be shut down until Tuesday after sundown whenthe fast is over. On the ninth of Av, the First Temple, built by King Solomon was destroyed by the Babylonians who sacked Jerusalem in 586 BCE. The Second Temple, which was built on the site of the First Temple, was completedin 516 BCE. During the Roman siege of Jerusalem in 70 CE, it was also destroyed on the same day. To mark the destruction of the two temples, rabbis declared the Ninth of Av to be a day of mourning for the Jewish people.