Big Jay is a 3,786 ft (1,154 m) mountain in the northern Green Mountains of Vermont, located on the border of Franklin and Orleans counties.
The summit of Big Jay is the highest point of Franklin County. Big Jay is flanked to the south by Little Jay (3,182 ft or 970 m), and to the northeast by Jay Peak (3,865 ft or 1,178 m), the highest summit of the Jay Peak complex. Jay Peak is named for John Jay (1745–1829) of New York, one of the "founding fathers" of the United States.
Big Jay stands within the watershed of the Trout River, a tributary of the Missisquoi River, which drains into Lake Champlain, thence into Canada's Richelieu River, the Saint Lawrence River, and into the Gulf of Saint Lawrence. The east and southeast sides of Big Jay drain into Jay Brook, which joins the South Branch…