 The primary highway leading from the New York ferry landing to US 9 near Plattsburgh, then Cumberland Head Road, was initially unnumbered.VT F-3 was maintained by the towns of South Hero and Grand Isle until June 20, 1957, when the state of Vermont assumed ownership and maintenance of the highway.The portion of the Adirondack Northway (I-87) between exits 36 and 39 was completed and opened to traffic .