 Almost 100 miles (161 km) to the north, it leaves the park and runs along or near Lake Champlain to Plattsburgh.North of there, it is once again a two-lane road all the way to Champlain, ending at an on-ramp to I-87 just shy of the border.Prior to the opening of the Cape May–Lewes Ferry in 1964, US 9 ended on Lafayette Street in Cape May, New Jersey.