The Ophel (Hebrew: עופל‎) or Ophlas, meaning fortified hill or risen area, is the biblical name given to a certain part of a settlement or city that is elevated from its surroundings. In the Bible the Ophel refers to the elevation in two cities: the City of David in the Old City of Jerusalem, and at Samaria, the ancient capital of the Kingdom of Israel. Ernest L. Martin asserts the controversial claim in his book, "The Temples that Jerusalem Forgot", that the Ophel Mound is the site of the First and Second Temples and what is called the Temple Mount today was in fact the Roman Fort Antonia.  The term can be seen as an equivalent to the Greek term Acropolis. 

 http://en.wikipedia.org/wiki/Ophel