Oglethorpe's agrarian balance was abandoned after the Georgia Trustee period. Additional squares were added during the late-18th and 19th centuries, and by 1851 there were 24 squares in the city. In the 20th century, three of the squares were demolished or altered beyond recognition, leaving 21. In 2010, one of the three "lost" squares, Ellis, was reclaimed. Most of Savannah's squares are named in honor or in memory of a person, persons or historical event, and many contain monuments, markers, memorials, statues, plaques, and other tributes.
All of the squares measure approximately 200 feet (61 m) from east to west, but they vary north to south from approximately 100 to 300 feet (91 m). Typically, each square is intersected north-south and east-west by wide, two-way streets. They are bounded to the west and east by the south- and north-bound lanes of the intersecting north-south street, and to the north and south by smaller one-way streets running east-to-west and west-to-east, respectively. As a result, traffic flows one way—counterclockwise—around the squares, which thus function much like traffic circles. 
All of the squares are a part of Savannah's historic district and fall within an area of less than one half square mile.  The five squares along Bull Street—Monterey, Madison, Chippewa, Wright, and Johnson—were intended to be grand monument spaces and have been called Savannah's "Crown Jewels." Many of the other squares were designed more simply as commons or parks, although most serve as memorials as well.