Philadelphians are fond of quoting a letter in which William Penn described his vision of a "greene country towne, which will never be burnt & always wholesome." Today, Philadelphia's public parks cover more than ten thousand acres--roughly 11 percent of the city's area. They encompass extensive woodlands and waterways as well as the largest collection of historic properties in the state of Pennsylvania, including the Fairmount Water Works, the Philadelphia Zoo (the oldest zoo in the United States), and the Philadelphia Museum of Art.

The Grid and the River is the product of Elizabeth Milroy's quest to understand the history of public green spaces in William Penn's city. In this monumental work of urban history, Milroy traces efforts to keep Philadelphia "green" from the time of its founding to the late nineteenth century. She chronicles how patterns of use and representations of green spaces informed notions of community and identity in the city. In particular, Milroy examines the history of how and why the district along the Schuylkill River came to be developed both in opposition to and in concert with William Penn's original designations of parks in his city plan.

Focusing on both the history and representation of Philadelphia's green spaces, and making use of a wealth of primary source materials, Milroy offers new insights into the city's political and cultural development and documents how changing attitudes toward the natural environment affected the physical appearance of Philadelphia's landscape and the lives of its inhabitants.