Bithron

bith'-ron (ha-bithron; holen ten parateinousan, literally "the entire (land) extending"; 2 Samuel 2:29, "the Bithron," i.e. the gorge or groove):

Does not seem to be a proper name; rather it indicates the gorge by which Abner approached Mahanaim. Buhl (GAP, 121) favors identification with Wady `Ajlun, along which in later times a Ro road connected `Ajlun and Mahanaim. Others (Guthe, Kurz. bib. Worterbuch, under the word) incline to Wady esh Sha`ib.