The Ophel (Hebrew: עֹ֫פֶל ‘ōp̄el), also Graecised to Ophlas, Is the biblical name apparently given to a certain part of a settlement or city that is elevated from its surroundings, and probably means fortified hill or risen area. In the Hebrew Bible the Ophel refers to a specific part in two cities: the extended City of David (the oldest part of Jerusalem), as in the Book of Chronicles and the Book of Nehemiah (2 Chronicles 27:3; 33:14, Nehemiah 3:26; 11:21), and at Samaria, the ancient capital of the Kingdom of Israel, mentioned in the Second Book of Kings (2 Book of Kings 5:24). The Mesha Stele is the only extra-biblical source using the word, also in connection to a fortified area.
Meaning of the term
Ophel, with the definite article ha-ophel, is a common noun known from two Ancient Semitic languages, Biblical Hebrew and Moabitic. As a place name or description it appears several times in the Hebrew Bible and once on the Mesha Stele from Moab. There is no ultimate agreement as to its exact meaning, and scholars have long been trying to deduce it from the different contexts it appears in. When used as a common noun, it has been translated as "tumors" (1 Samuel 5:9, 12; 6:5), and in a verbal form it was taken to mean "puffed up" (Habakkuk 2:4), this indicating that the root might be associated with "swelling". When referring to a place, it seems from the context to mean either hill, or fortified place, or a mixture of the two, i.e., a fortified hill, and by considering the presumed meaning of the root, it might signify a "bulging or rounded" fortification.
Biblical verses in which it has been translated either as "fortified place " (tower, citadel, stronghold etc.) or "hill" are 2 Kings 5:24, 2 Chronicles 27:3 and 33:14, Isaiah 32:14, Nehemiah 3:26 and 11:21, and Micah 4:8. On the Mesha Stele, named for the king of Moab who erected it, Mesha says: "I built Q-R-CH-H (? Karhah), the wall of ye'arim [forests], and the wall of ophel and I built its gates and I built its towers." Here ophel is commonly translated as "citadel".
The location of the Ophel of the Hebrew Bible is easy to make out from the references from 2 Chronicles 27:3; 33:14 and Nehemiah 3:26, 27: it was on the eastern ridge and south of the Temple, and probably near the middle of the southeastern hill (i.e., the eastern ridge segment starting below the saddle south of the Herodian Temple Mount, and stretching down to the King's Garden). Therefore, the use of the term "Ophel ridge" for the entire southeastern hill including the saddle area seems to be wrong.
Two kings of Judah, Jotham and Manasseh, are described to have massively strengthened the fortifications at "Ophel" (2 Chronicles 27:3 and 33:14), leading to the conclusion that this must have been an area of great strategic importance, and either very close to or identical with the "stronghold of Zion" conquered and reused by King David (2 Samuel 5:7).
Josephus, writing about the First Jewish–Roman War (66–70 CE), uses the Graecised form "Ophlas", and places it slightly higher up the eastern ridge from the First Temple-period Ophel, touching the "eastern cloister of the temple" (Jewish Wars, V, iv, 2 ) and in the context of "the temple and the parts thereto adjoining, .... and the .... 'Valley of the Cedron'" (Jewish Wars, V, iv, 1 ).
- Bible Hub: Ophel. Excellent overview, based on critical analysis of the texts; only partially outdated (article predates most excavations on the eastern hill).
- Jerusalem Archaeological Park. History of archaeological investigation 1838-2000. Does not include important new findings by Eilat Mazar.
- Jerusalem 101: Ophel. Location of the Ophel: plans, models, some photos. Some mix-up of slightly differing First and Second Temple-period locations. 
- George Wesley Buchanan, Misunderstandings About Jerusalem's Temple Mount, Washington Report on Middle East Affairs, August 2011, Pages 16, 64. Supports the very controversial "southern location" theory placing both Jerusalem Temples above the Gihon Spring, rather than on the Temple Mount. 
- Another "southern location" theory article (dead link, as of August 2016) 
- Lightfoot, John. 2007. From the Talmud and Hebraica, Vol. 1 (reprint). New York, New York: Cosimo. p. 62. ISBN 978-1-60206-406-5
- Freedman, David Noel; editor. 2000. Eerdmans Dictionary of the Bible. Grand Rapids, Michigan: Wm. B. Eerdmans Publishing Co., p. 990. ISBN 0-8028-2400-5
- Masterman, Ernest William Gurney (1915). "Ophel". In James Orr. International Standard Bible Encyclopedia (first ed.). Chicago: Howard-Severance Co. Retrieved 2 August 2016.
- "The Mesha Stele: Traduction du texte". Louvre, official website (in French). Translated by André Lemaire, 1986. Musée du Louvre, Paris. Retrieved 2 August 2016.
- The Wars Of The Jews, Book V, Chapter IV, paragraph 2. At sacred-texts.com 
- The Wars Of The Jews, Book V, Chapter IV, paragraph 1. At sacred-texts.com