'Memorial' in the Bible

Joshua told them, "Cross over again in front of the ark of the LORD your God into the middle of the Jordan River. Then each of you pick up a stone on his shoulder with which to build a memorial, one for each of the tribes of Israel.

then you'll say to them, "Because the waters of the Jordan River were cut off in front of the Ark of the Covenant of the LORD. When it crossed the Jordan River, the waters of the Jordan were cut off.' So these stones will become a memorial to the Israelis forever."