The western terminus of NY 301 is at a four-way junction with NY 9D in Cold Spring. At the intersection, Morris Avenue enters from the north, Chestnut Street comes in from the south, and Main Street enters from the west and leaves to the east on NY 301. The route climbs a hill into the Philipstown village of Nelsonville, where it remains Main Street until transitioning into Cold Spring Carmel Road and passing near the southeast border of the Hudson Highlands State Park. It crosses US 9, locally Albany Post Road, at Mekeel Corners and continues northeast into the woods of the Clarence Fahnestock State Park.