From BiblePortal Wikipedia

Hastings' Dictionary of the Bible [1]

HACHILAH (  1 Samuel 23:19;   1 Samuel 26:1;   1 Samuel 26:3 ). A hill in which David hid, and on which, during his pursuit, Saul pitched his camp, near the wilderness of Ziph. Ziph is mod. Tell ez-Zîf , to the S. of Hebron. Conder suggests that Hachilah may be the hill Dahr el-Kôlâ , but this is perhaps rather far to the east.

W. Ewing.

Morrish Bible Dictionary [2]

Hill near Ziph in Judah, described as being 'before' or 'on the south of ' Jeshimon. David resorted there when pursued by Saul, and there David spared Saul when he was in his power.  1 Samuel 23:19;  1 Samuel 26:1,3 . Identified by some with Dhahret el Kolah, 31 28' N, 35 13 E.

People's Dictionary of the Bible [3]

Hachilah, Hill of ( Hăk'Al-Ah ), The Darksome Hill. A place in Judah near Ziph, and where David with his 600 followers hid.  1 Samuel 23:19; compare 14, 15, 18; 26:3.

Easton's Bible Dictionary [4]

 1 Samuel 23:19 1 Samuel 26:13-25

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [5]

(Heb. Chakilah', חֲכילָה . according to Gesenius, Darksome; according to F Ü rst, Drought; Sept. Ε᾿Χελά v.r. Χελμάθ ), the descriptive name of a well Wooded hill ( גַּבְעָה ) near ("on the south of," "before," "by the way of") the wilderness ("Jeshimon") of Ziph, where David lay hid, and where Saul pitched his tent at the information of the Ziphites ( 1 Samuel 23:19;  1 Samuel 26:1;  1 Samuel 26:3). This is doubtless the Tell Zif reported by Dr. Robinson (Researches, 2, 190, 191) as "a round eminence situated in the plain, a hundred feet or more in height," with a level plot on the top, apparently once enclosed by a wall, and containing several cisterns; lying a short distance west of the site of the town of Ziph. (See Ziph). The identification proposed by Schwarz (Palest. p. 113) with "the village Beth-Chachal, 21 miles west of Hebron," is unsupported and out of place.