If there is ever a Third World War, there is a good chance it will start at the Temple Mount/Haram al-Sharif complex in Jerusalem.
King Solomon built the First Temple on this spot 3000 years ago. This Temple was destroyed and the Jews were exiled to Babylonia in 586 BCE. After Cyrus the Great of Persia conquered Babylon he encouraged the Jews to return to their homeland and rebuild the Temple. This they did, but the Second Temple was destroyed and the Jews were once again sent into exile by the Romans, in 70 A.D.