Where the Great Iroquois Trail turned east, on the 21st day of September, 1779, Lieutenant-Colonel William Butler's force of 600 men from Major-General John Sullivan’s army passed on its march to the Cayuga castle on the Great Gully, and Colonel Peter Gansevoort's detachment of 100 New York troops, which had accompanied Butler's force from the foot of Seneca Lake, left it there and proceeded eastward along the trail to the Mohawk and Albany.