The priests who bore the ark of the covenant of Yahweh stood firm on dry ground in the midst of the Jordan; and all Israel passed over on dry ground, until all the nation were passed clean over the Jordan.
The waters standing up in a heap is, of course, exactly what waters always do behind a dam, and, since this miraculous stoppage took place miles above where the Israelites were, they might not have known exactly where the waters were gathered together in a heap until some time later. Joshua's knowledge of this came in advance from a direct revelation of God. Significantly, the place identified as Adam is the precise location of the tallest of those great mud cliffs that line the banks of the Jordan.