The journey had been particularly severe and wearing upon the animals, and their food supply was found insufficient. Arriving about north of Fort Reid on September 24, 1779, they were obliged to dispose of a large number of sick and disabled horses. The number of horses was so great that they were quite noticeable, and the native Iroquois collected the skulls and arranged them in a line along the trail. From that time forward, that spot was referred to as the "Valley of the Horses' Heads" and is still known by the name given to it by the Iroquois.