Paved bike path. Be prepared to see a lot of Marlboro & Hudson. I didn't see any parking on the Marlboro side where directions take you, ended up Peking t hospital bed walking 1/4 mile down. Lots of parking on Hudson end on Main St.
I only completed the first half of the trail. the pavement was mostly smooth and wide enough for bikers and walkers. there were some beautiful views of lakes in the beginning. Mile 3.5-4 was a bit more in the city. Nice ride