The Thompson Hill Common (or The Green) is the focal point of the Thompson Hill National Register Historic District. It is a long, triangular greensward containing about 2.5 acres and bounded by Route 193 on the east, Route 200 on the north and Chase Road on the west. Bates Avenue connects Route 200 and Chase Road, thereby dividing it in to two parts.

The well-maintained green slopes slightly to the southeast. It is planted with healthy, mature, shade trees including sugar maple and silver maple (and one elm) primarily along Route 200 and Chase Road between Bates Avenue and Route 193. Other than the trees and a war monument, the green remains relatively unimproved. There are no benches, no paths and no curbs around the edges, which has resulted in erosion of the green along Route 193 in front of the library where people park. The granite and bronze war memorial, located near Route 193, honors those who fought and died in the Spanish American War and the Civil War (when 235 soldiers from the area lost their lives).

Until 1987, Bates Avenue continued across Route 200 and connected with Route 193 and creating a tiny triangular-shaped plot bounded by Route 193, Bates Avenue, and Route 200, locally termed "the Heater Piece". The road was replaced with a pedestrian path. Although the Heater Piece has been privately owned at least since 1803, visually it serves as an extension of the green. This is especially true because of the location of the town pump at the northern tip.

The streetscape is comprised of substantial and often impressive examples of residential and institutional buildings dating primarily from the late 18th century to the mid-nineteenth century. The only commercial building is the Vernon Stiles Inn (1814) on the northeast corner of Route 200 and 193, built on the site of an earlier inn after the completion of the two highways (then "turnpikes"). Across Route 200 and facing the green is the Thompson Congregational Church (1856) built in the Italianate style. It is best viewed from the opposite end of the green (where the Old Town Hall is located) at the intersection of Route 200 and Chase Road where the classic image of the New England Green with the grass in the foreground and the white church with the tall steeple in the background can be appreciated.

Other institutional buildings surrounding the green include the Thompson Public Library (1902), Old Town Hall (1842), Academy, the post office, and the Marianapolis Preparatory School, a complex of buildings set back from Chase Street and entered by a drive opposite Bates Avenue. The post office is a recent addition to the green and has a very plain, functional appearance. The Academy is located next to the church and is a rather severe, brick, Greek Revival representative of its type. It is vacant and appears to be deteriorating from neglect.

The remaining buildings around the green, all residential, are fine homes erected by people who lived in Thompson when it prospered during the time it was an important crossroads community before the advent of the railroad. The green and its surrounding streetscape with few exceptions represent the town of Thompson as it appeared then.