This large (approximately 2-acre) parklike green is defined by High Street to the south, Water Street to the west, Broad Street to the north, and Main Street to the east. The green is dominated by the Beaux-Arts Library located in the center. Built in 1899, the building is constructed of yellow brick with granite trim. An ornamental doorway flanked by a pair of polished granite Ionic columns embellishes the south façade. An addition to the north side was erected in 1955.

A horseshoe-shaped driveway extends from High Street to the library building. Flanking the driveway at High Street are a pair of stone pillars, which each support a cannonball. The cannonballs are presumably from the siege of 1814. The WPA Connecticut guide reports that "cannonballs from the King's Navy which fell harmlessly in the woods and fields about the town are among Stonington's most valued relics."

Concrete walls run diagonally from each corner of the square, meeting at the library. Concrete walks, adjacent to the streets, enframe the square. The square is raised slightly above street level by a curved granite curb. Ornamental lights line the walks, and benches are located at regular intervals.

Numerous mature shade trees grace the square. Among them are oak, cherry, maple, ash, horse chestnut, and birch varieties.

Facing the square on Main, High, and Water Streets are many well-preserved 19th century homes. Facing the square on Broad Street is a Colonial revival post office and a contemporary church (St. Mary's).