The Seaway Trail continues north on Route 104 to NY 18F in the village of Lewiston. Route 18F jogs west and north through Lewiston and then north to Youngstown. North of Youngstown, Route 18F comes very close to the mouth of the Niagara River and swings eastward, now following the Lake Ontario shoreline. Route 18F ends a short distance east of the river's mouth at NY 18. Route 18 hosts the Seaway Trail for the rest of its length in Niagara County, which is almost .