Joshua 4:8-9
Joshua 4:8-9 NCV
So the Israelites obeyed Joshua and carried twelve rocks from the middle of the Jordan River, one rock for each of the twelve tribes of Israel, just as the LORD had commanded Joshua. They carried the rocks with them and put them down where they made their camp. Joshua also put twelve rocks in the middle of the Jordan River where the priests had stood while carrying the Ark of the Agreement. These rocks are still there today.