 NY 9N continues to the west for 12 miles ( 19 km ) through deep , narrow valleys to Keene , where it meets NY 73 north of Keene Valley . Here , NY 9N turns north , joining NY 73 for 2 miles ( 3 @.@ 2 km ) to the hamlet of Keene , located on the east branch of the Ausable River . NY 73 heads off to the west from this point toward Lake Placid ; however , NY 9N follows the river northward into the town of Jay , where it intersects the east end of NY 86 . The highway continues alongside the western bank of the river branch to the hamlet of Au Sable Forks , situated on the Essex – Clinton County line and at the point where the Ausable River 's east and west branches come together . 
