The Old Mill River Area is a historic district in Northampton that encompasses the industrial and residential development along the Mill River from the 18th to the 20th centuries. The area includes several mill buildings, workers' housing, churches, schools, and bridges that reflect the economic and social history of the city. The area was listed on the National Register of Historic Places in 1982. 

The Manhan Rail Trail traverses the area.

The AllTrails website has a description and map of a hike on the Manhan Rail Trail.