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Watson's Biblical & Theological Dictionary [1]

Ακρα . This Greek word signifies, in general, a citadel. The Syrians and Chaldeans use הקרא , in the same sense. King Antiochus gave orders for building a citadel at Jerusalem, north of the temple, on an eminence; which commanded the holy place; and for that reason was called Acra. Josephus says, that this eminence was semicircular, and that Simon Maccabaeus, having expelled the Syrians, who had seized Acra, demolished it, and spent three years in levelling the mountain on which it stood; that no situation in future should command the temple. On mount Acra were afterward built, the palace of Helena; Agrippa's palace, the place where the public records were lodged; and that where the magistrates of Jerusalem assembled.

Hastings' Dictionary of the Bible [2]

ACRA . See Jerusalem, I. 3 , II. 2 .

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [3]

( ῎Ακρα ) , a Greek word, signifying a Summit or Citadel, in which sense its Hebraized form Chakra ( חִקְרָא ) also occurs in the Syriac and Chaldaic (Buxtorf, Lex. Talm. col. 818). Hence the name of Acra was acquired by the eminence north of the temple at Jerusalem, on which a citadel was built by Antiochus Epiphanes, to command the holy place ( 1 Maccabees 3:45;  1 Maccabees 4:2;  1 Maccabees 4:41;  1 Maccabees 6:18;  1 Maccabees 6:26;  1 Maccabees 6:32;  1 Maccabees 9:52;  1 Maccabees 10:6;  1 Maccabees 11:41;  2 Maccabees 4:12;  2 Maccabees 4:27, etc.). It thus became, in fact, the Acropolis of Jerusalem (see Michaelis, in Macc. p. 30 sq.; Crome, in the Hall. Encykl. 2, 291 sq.). Josephus describes this eminence as semicircular (see Reland, Paloest. p. 852); and reports that when Simon Maccabaeus had succeeded in expelling the Syrian garrison, he not only demolished the citadel, but caused the hill itself to be levelled, that no neighboring site might thenceforth be higher than or so high as that on which the temple stood. The people had suffered so much from the garrison, that they willingly labored day and night, for three years, in this great work (Ant. 13, 6, 6; War, 5, 4, 1). At a later period the palace of Helena, queen of Adiabene, stood on the site, which still retained the name of Acra, as did also, probably, the council-house, and the repository of the archives (War, 6, 6, 3; see also Descript. Urbis Ierosolmyoe, per J. Heydenum, lib. 3, cap. 2).

A good deal of controversy has lately arisen as to the position of this eminence, Dr. Robinson (Bib. Res. 1, 414; new ed. 3, 207-211) strongly contending for the sloping eminence now occupied by the Church of the Holy Sepulchre, and others (especially Williams, Holy City, 2, 25, 49) placing Acra more north-wardly from the temple. The latter position, in the middle of the Mohammedan quarter, on the whole, seems best to accord with the present state of the surface and the ancient notes of place (see Strong's Harmony and Expos. of the Gospels, Append. 2, p. 4, 5); especially with Josephus's statements (War, 5, 4, 1) respecting the valley of the Tyropoeon (q.v.). (See Jerusalem).

A place by the name of Acra ( ῎Ακρα ) is mentioned by Josephus (War, 2, 2, 2) as having been taken by Simon Maccabaeus, in connection with Gazara, Joppa, and Jamnia; which some suppose to mean Ekron (by a change of reading), while others take the word in the ordinary sense of tower. The passage is evidently parallel with  1 Maccabees 14:7, where Simon is said, after having taken Gazara and Bethsura, to have cleansed "the tower" ( Ἄκρα ); which, by a comparison with chap. 13:49, appears to mean no other than the above fortress in Jerusalem. See Baris

For the Acra or Acre (Hebraized אקרי by Benjamin of Tudela) of the Crusades, (See Accho).