is a town in Franklin County, Massachusetts, part of the Pioneer Valley. The population was 3,777 at the 2000 census. It is part of the Springfield, Massachusetts Metropolitan Statistical Area.
Sunderland was first settled in 1713 and was officially incorporated in 1714. It was first known as Swampfield, a name which is now honored by Swampfield Road, but the name was changed to attract more residents. It was renamed in honor of Charles Spencer, the Earl of Sunderland. Historically, the land was largely used for farming.
According to the United States Census Bureau, the town has a total area of 14.8 square miles (38.3 km²), of which, 14.4 square miles (37.3 km²) of it is land and 0.4 square miles (1.1 km²) of it (2.77%) is water.
Sunderland is on the east bank of the Connecticut River, which can be crossed by the Sunderland Bridge. It borders the towns of Deerfield, Whately, Hadley, Leverett, Montague and Amherst. Mount Toby, a prominent conglomerate mountain with a firetower lookout, stands at the east border of the town and is traversed by the 47 mile Robert Frost Trail. The mountain is known for its waterfalls, scenic vista, and biologically diverse ecosystem.