Joshua 4:21-23

He said to the Israelites, “In the future your children will ask their parents, ‘What about these stones?’ Then you will let your children know: ‘Israel crossed over the Jordan here on dry ground.’ This was because the LORD your God dried up the water of the Jordan before you until you crossed over. This was exactly what the LORD your God did to the Reed Sea. He dried it up before us until we crossed over.