Hudson River Trail is a 2 mile loop trail located near Warrensburg, NY. The trail is good for all skill levels and primarily used for snowshoeing.
Directions for this trail on this site are wrong. I followed the directions and wasted 45 minutes not finding it. On my way home on a different road, I found it accidentally.
It's on Golf Course Road in Warrensburg, NY. Probably in the same location on the river but on the opposite bank... but it's probably 20 miles by road.