Charles Ellicott Commentary Joshua 8:11

"And all the people, [even] the [men of] war that were with him, went up, and drew nigh, and came before the city, and encamped on the north side of Ai: now there was a valley between him and Ai." — Joshua 8:11 (ASV)

On the north side. —The lurking-place of the thirty thousand was on the west side, between Bethel and Ai.

There is a ravine called the Wady Maheesin which runs nearly east and west, on the north of et-Tel. Probably Joshua’s main body took up a position on the rising ground to the north of this ravine, for it is added, the ravine (or Gai) was between them and Ai.