Ai was a place in central Canaan. It is first mentioned in the Bible in Genesis 12:8 as a place where Abram camped during his journey toward the land God promised in Genesis 12:1: “Go from your country, your people and your father’s household to the land I will show you.” When Abram reached Ai, he built an altar and “called upon the name of the Lord.” The name Ai means “heap of ruins” (Joshua 8:28).

According to Joshua 7:2, Ai was a Canaanite city located approximately two miles east of Bethel (Joshua 10:1). The ruins of the city now lie beneath the modern archaeological site of Et-Tell on a slope leading from the Jordan Valley to Bethel. Ai is notable for being the scene of a humiliating Israelite defeat as the small city of Ai routed the Israelites and inflicted three dozen casualties. The loss at Ai was due to the sin of Achan (Joshua 7:1–5). In direct defiance of God’s command to keep nothing for themselves from the wicked city of Jericho (Joshua 6:19), Achan had kept a robe, two hundred shekels of silver, and a fifty-shekel bar of gold and hid it all in a hole he had dug within his tent. Achan kept his theft a secret until Israel was defeated at Ai. God then revealed to Joshua the cause for this defeat, and Achan, his family, and everything he owned was destroyed at God’s command (Joshua 7:25–26).

Once the sin had been purged from the camp and Achan had been punished, God gave Joshua victory over Ai (Joshua 8:1–29). After drawing the men of Ai out of the city and ambushing them, Israelite warriors captured the king and brought him to Joshua (Joshua 8:23), who impaled him and left his body on public display as a testament to Israel’s great triumph over the enemies of the Lord. The body of the king of Ai was left hanging until evening, at which time it was thrown in the gate of Ai and piled over with rocks (verse 29). After first tasting terrible defeat at Ai due to hidden sin, Israel learned about the power of purging sin from their midst so that the Lord could fight for them (see Joshua 23:3).

The region around Ai became part of the land given to the tribe of Benjamin in the distribution of the Promised Land (Ezra 2:28). Ai was the second Canaanite city taken by Israel in its conquest of the Promised Land, the first being the great victory at the battle of Jericho.

The prophet Isaiah mentions a rebuilt Ai in Isaiah 10:28, calling it Aiath.