Joshua 4:8

And the children of Israel did so as Joshua commanded, and took up twelve stones out of the midst of Jordan, the twelve men acting as the representatives of the entire host or congregation, as the Lord spake unto Joshua, according to the number of the tribes of the children of Israel, and carried them over with them unto the place where they lodged, where camp was pitched that evening, and laid them down there, in the form of a rough monument.