The Temple Mount is a platform in the Old City of Jerusalem, on which the First and Second Temples once stood. The proncipal buildings on the site today are the Dome of the Rock and the Al-Aqsa Mosque. The Mount is surrounded by massive retaining walls constructed by Herod the Great in about the year 19 BC.
Under the Ottomans, Jews were not allowed to enter the Temple Mount, but were permitted to worship at the Western Wall ("the Wailing Wall"), part of the Herodian retaining structure.
Since the Six Day War, Israel has been responsible for security on the Temple Mount, but administration has been in the hands of the Jerusalem Islamic Foundation (the "Waqf"), with political control nominally exercised by the King of Jordan. Non-Muslims may now visit the Temple Mount but are not allowed to pray there.