Joshua 8:10-13

Joshua arose early in the morning and mustered the people and went up, he and the elders of Israel, before the people to Ai. And all the fighting men who were with him went up and drew near before the city and encamped on the north side of Ai, with a ravine between them and Ai. He took about 5,000 men and set them in ambush between Bethel and Ai, to the west of the city. So they stationed the forces, the main encampment that was north of the city and its rear guard west of the city. But Joshua spent that night in the valley.