The square is one of the five original open-space parks planned by William Penn and his surveyor Thomas Holme during the late 17th century.

[3] William Rittenhouse's original paper-mill site is known as Rittenhousetown, located in the rural setting of Fairmount Park along Paper Mill Run.

David Rittenhouse was a clockmaker and friend of the American Revolution, as well as a noted astronomer; a lunar crater is named after him.

Having thus set the patrician residential tone that would subsequently define the Square, he divided the rest of the land into generously proportioned building lots and sold them.

Sold after the congressman's death, the Harper house became the home of the exclusive Rittenhouse Club, which added the present facade in c. 1901.

From 1876 to 1929, Rittenhouse Square was home to several wealthy families including Pennsylvania Railroad president Alexander Cassatt, real estate entrepreneur William Weightman III, department store founder John Wanamaker, Philadelphia planning commission director Edmund Bacon and his son, actor Kevin Bacon, as well as others.

After World War II, Rittenhouse Square's Victorian mansions began to be replaced with high-rise residential and office buildings such as Claridge and Savoy.

Journalist and author Jane Jacobs wrote about two main ideas in Cret's redesign: intricacy and centering.

The park is a popular dog walking destination for area residents, as was shown in the fictional film In Her Shoes.

The Square was discussed in a favorable light by Jane Jacobs in her seminal work, The Death and Life of Great American Cities.

Delancey Place is a quiet, historical street lined with Civil War-era mansions and the setting for Hollywood movies, located only two blocks south of the square.

The PATCO Speedline, a rapid transit system connecting Philadelphia and Southern New Jersey, has its western terminus at 16th and Locust Sts., two blocks east of the Square.