Joshua 6:4, 8-9

Seven priests shall bear seven trumpets of rams’ horns before the ark. On the seventh day you shall march around the city seven times, and the priests shall blow the trumpets.

And just as Joshua had commanded the people, the seven priests bearing the seven trumpets of rams’ horns before the LORD went forward, blowing the trumpets, with the ark of the covenant of the LORD following them. The armed men were walking before the priests who were blowing the trumpets, and the rear guard was walking after the ark, while the trumpets blew continually.