Location
The Town of Plainfield is situated in the scenic Berkshire Highlands where Hampshire County merges into neighboring Franklin and Berkshire Counties. Plainfield is part of the Hilltowns of Western Massachusetts.
Plainfield sits 1620′ above sea level, and the peaks of West Mountain (at 2125′) are the highest elevation in Hampshire County.
According to the United States Census Bureau, the town has a total area of 21.3 square miles of which 21.0 square miles is land and 0.2 square miles (0.99%) is water.
Plainfield's waterways serve as the headwaters of the Westfield and Deerfield rivers.
Plainfield is bordered by the towns of Cummington, Ashfield, Hawley, Savoy, and Windsor.