Joshua 6:4-7

Also, seven priests shall carry seven trumpets [made] of rams’ horns ahead of the ark; then on the seventh day you shall march around the city seven times, and the priests shall blow the trumpets. When they make a long blast with the ram’s horn, and when you hear the sound of the trumpet, all the people shall cry out with a great shout (battle cry); and the wall of the city will fall down in its place, and the people shall go up, each man [going] straight ahead [climbing over the rubble].” So Joshua the son of Nun called for the priests and said to them, “Take up the ark of the covenant, and have seven priests carry seven trumpets made of rams’ horns ahead of the ark of the LORD.” He said to the people, “Go forward! March around the city, and let the armed men go ahead of the ark of the LORD.”