The trail crosses or nears several rivers, streams, and ponds.
The Rail Trail Pond is at the north end of the trail in Nashua near the Gilson Road parking lot.
The East Pepperell wetlands lie to the east of the trail about midway between River Street in Dunstable and Lowell Street in Pepperell. You might see turtles resting on logs within the pond.
Nissitissit River joins the Nashua River near the trail in East Pepperell. Although this is not visible from the rail trail, you can see this from the dirt trails running alongside the trail in East Pepperell.
Nashua River runs generally to the west of the trail with the best views south of Railroad Square in Pepperell.
Nod Brook flowing east from the Nashua River crosses under the trail south of Sandy Hill Road in Groton. Look for a small sign on the east side of trail.
James Brook crosses the trail south of Broadmeadow Road. A small sign marks the point where it crosses under the trail at Station Avenue.
Groton School Pond abuts the trail north of Smith Street in Groton. You may see beaver lodges in the pond.
