Mill Plain Green is located northwest of Fairfield in an area that has always been known as Mill Plain. It is situated at the intersection of Sturges and Mill Plain Roads and bordered by Mill Plain Green on the north. On the north and west are residences built during the 18th and 19th centuries. The most visually distinctive structure is the large Sturges Cottage, a fine and early example of American Gothic architecture. It was built in 1840 for Jonathan Sturges, a successful New York City businessman and a summer resident of Stratford. To the west of the green is a complex of one- and two-story structures that are all part of a chronic convalescent hospital. The offices are in a large, two-story Colonial Revival structure. The rest are in flat-roofed institutional buildings. They are all set back from the road to allow for parking in front. The only redeeming feature is a stone wall along the street in front of the parking lots that helps to provide boundaries for the green.

The green is flat and somewhat uneven. It is randomly planted with shade trees except for one evergreen near the center. North of it is a flagpole. Along Sturges Road is an asphalt sidewalk and a mailbox near the southern tip. Close to the intersection is a wooden sign announcing the green which is underplanted with shrubs in need of care. To the north of it is a cast iron sign marking the site of Trinity Church, built on the green c. 1779. Near it is an oak tree with a small plaque at its base identifying it as tercentenary oak tree.