Signal Mountain in Vermont’s Groton State Forest stands in Caledonia County near Spruce Mountain and Butterfield Mountain, and its chief significance is as a regional drainage divide. Water from its north and east slopes flows through Noyes Pond or Heath Brook into the South Branch of the Wells River and then the Connecticut River system, eventually reaching Long Island Sound. Its south side drains into the Waits River, also part of the Connecticut watershed. In contrast, water from the west side passes through Great Brook to the Winooski River, Lake Champlain, and ultimately the Gulf of Saint Lawrence in Canada.