The three-mile trip north, to a point just north of a trestle over the Hudson, is slightly uphill, with a grade of less than 1 percent. Harte said customers as old as 87 and as young as 2 had made it up and back without problems. The business has special seat harnesses for young children.

What goes up must come down, so the ride back is a breeze, with bikes rolling on their own in places.

“There is a slight downhill you will appreciate on the way back,” Harte said.

Those who want to pedal faster for a better workout can go at their own pace, and those who want a leisurely pace can go slower, Harte said.

The bikes can also be propelled easily by parents with young kids, who are on bikes but can’t pedal. One person pedaling can move the bike along at a decent pace, depending on the weight of passengers.

Guides Isa O’Brien, Paul O’Brian and Nick Lascala worked with Harte to shepherd the riders up and back. There is one road crossing, near Barton Mines, where they hop off their bikes to make sure no traffic is approaching.

The aluminum frame bikes, handmade by Harte and associates in Vermont, are light enough for Harte’s crew to lift them off the rails and place them back on to turn around for the trip back.