Joshua 8:29

And the king of Ai he hanged on a tree until eventide: and as soon as the sun was down, Joshua commanded that they should take his carcase down from the tree, and cast it at the entering of the gate of the city, and raise thereon a great heap of stones, that remaineth unto this day.

The verse belongs to the account of Israel's conquest of Ai, a conquest accomplished by marching out from Gilgal. Gilgal was Israel's first encampment in the promised land. It was linked with several important events in Israel's early life in the promised land.