Rode the entire Northern Tier west to east many years ago. Nice route overall. The trip up the river to Niagara Falls was fun. It used the Erie Canala tow path from Lockport, NY. Didn't like that all that much in places due to the surface condition, and I hear there are sections that were recently damaged by flooding. There are parallel roads you can follow. From somewhere east of Rochester, the route headed up to Lake Ontario and then east to Sodus Point and Booneville. You eventually cross the Adirondacks and end up doing a screaming descent into Ticonderoga, where you catch a cable ferry to VT. The VT section was very nice. In the Middlebury area we went off route to find camping and ended up doing Brandon Gap instead of Middleburry Gap. It was the one climb on the entire trip I thought I might have to walk a portion of. The final section is very steep. Woodstock, VT is a crazy town. In NH, you get to ride the Kagamagus (SP?) Highway (between Lincoln and Conway) through the White Mountain National Forest. Very pretty. The part I didn't like the most was in ME. The U.S. 1 corridor is very busy and noisy. There is a great state park in Camden. Bar Harbor is very crowded up through Labor Day.