Edge Cities


Edge cities, as they came to be called, emerged on the peripheries of older urban centers in the last part of the twentieth century. As defined by journalist Joel Garreau (b. 1948), they contained at least five million square feet of leasable office space, 600,000 (or more) square feet of leasable retail space, “more jobs than bedrooms,” and a wide offering of occupational and recreational opportunities. Whether a singular municipality or a group of intermingling towns (at times spanning more than one state), they appeared nationwide, including several within Greater Philadelphia. By the 2010s, however, many undeveloped areas between the region’s older and edge cities themselves also clustered residents, jobs, and places for leisure, thereby challenging Garreau’s widely cited definition.

Garreau popularized the term “edge city” in his 1991 book Edge City: Life on the New Frontier. He argued that the phenomenon grew out of postwar suburbanization, the building of interstate highways, and “new towns” conceived by planners including Ray Watson (1926-2012) and Robert E. Simon (1914-2015). Their proliferation accelerated urban decentralization while at the same time reflecting the shift from manufacturing to service- and information-based economies. In some cases, they developed in rural areas or near existing transportation infrastructure (rail lines and secondary highways) while others resulted from new roadways, shopping malls, and the embrace of “car culture.”

color photo of pedestrian walking past shops in downtown Ardmore, PA
Ardmore, Pennsylvania, is an example of a city that has prospered on the periphery of Philadelphia, with a robust shopping and dining scene. (Photograph by R. Kennedy for Visit Philadelphia)

Following World War II, population and job losses severely damaged Philadelphia and Chester, Pennsylvania; Camden and Trenton, New Jersey; and Wilmington, Delaware. At the same time, early postwar suburbs, such as Levittown and Springfield, Pennsylvania; Duncan Woods and Sherwood Park, Delaware; and Willingboro, New Jersey, accommodated a growing middle-class in communities that later included their own shopping centers, churches, and schools. Yet many residents still commuted to central cities for work and leisure activities. By the early 1960s, following the opening of new interstate highways, edge cities formed in rural portions of Burlington and Camden County, New Jersey; New Castle County, Delaware; and in Chester, Bucks, and Montgomery Counties to the north and west of Philadelphia. In the process, Greater Philadelphia’s older cities struggled to remain relevant.

an artists' conception of the Cherry Hill Mall. It is drawn from an aerial perspective. In the center is a cluster of large, flat white buildings. The buildings are surrounded by extensive surface parking lots full of parked cars.
The Cherry Hill Mall was one of the major factors in the rapid, edge city-style development of Cherry Hill, New Jersey. Cherry Hill became home to corporate parks, retail chains, suburban developments, and thoroughfares as people were enticed to live and work there. This image is an artists’ rendering of the mall prior to its construction. (Special Collections Research Center, Temple University Libraries)

Along with expressways, many edge cities owed their founding to the modern shopping mall. In 1961, the Cherry Hill Mall, then the nation’s largest enclosed shopping facility, opened in Delaware Township, Camden County. Designed by Victor Gruen (1903-80), it included dozens of stores, a food court, tropical atrium, art exhibits, a four-hundred-seat auditorium, and acres of free parking. Located four miles from the interchange of US Route 30, US Route 130, and New Jersey Route 38, the mall grew into one of South Jersey’s main commercial centers and over time drained economic activity from nearby Camden and Philadelphia’s aging department stores. The town of Cherry Hill, renamed from Delaware Township the same year, emerged as a prosperous edge city, luring pharmaceutical firms, auto dealerships, corporations such as Subaru of North America, and an NJ Transit rail stop. In 2003, demolition of its sixty-year-old horse track commenced to make way for Garden State Park, a mixed-use complex of condominiums, restaurants, and upscale stores totaling more than one million square feet. The building of the New Jersey Turnpike in the 1950s and the opening of the Moorestown Mall in 1963 boosted the Moorestown-Mt. Laurel area to the east in Burlington County. Bisected by I-295 and the New Jersey Turnpike, the affluent edge city attracted college campuses, waterparks, corporate tenants, and upscale restaurants.

Chester and Montgomery Counties

Upon completion of the Schuylkill Expressway (I-76), edge cities developed in Chester and Montgomery Counties. In 1963, the King of Prussia Mall opened near Valley Forge. Expanded over the years, the shopping complex located at the junction of I-76, the Pennsylvania Turnpike, and US Routes 202 and 422, ranked in 2017 as the nation’s second-largest mall. In addition King of Prussia hosted more than sixteen thousand jobs, in health care, utilities, and energy, among others. To suit convention traffic, the 240,000-square foot Greater Philadelphia Exposition Center opened in 2009. For entertainment and gaming, the Valley Forge Casino Resort opened in 2012 five miles away.

Conshohocken, a former factory city eight miles east, by the late 1990s had attracted chain hotels, apartments and restaurants, and the headquarters of design firms and security companies. Combined with nearby Norristown (the Montgomery County seat) the three cities formed a metropolitan area in its own right, with links to central Philadelphia by trains, bus lines, and several roads. In nearby Malvern, Pennsylvania, the Great Valley Corporate Center opened in 1974. Touted by then-president Ronald Reagan (1911-2004) in 1985 as the “workplace of the future,” the expanded complex employed more than twenty thousand and was home to biotech, financial, and medical firms. In 2015, plans unfolded to redesign the area into a walkable, mixed-use community with over one million square feet of stores, offices, and condominiums. Located just north of US Route 202 and US Route 30 and serviced by SEPTA regional rail, the Malvern area also included Paoli and Exton. Elsewhere in southeastern Pennsylvania, the Warminster-Willow Grove and the Bensalem-Levittown-Langhorne areas experienced edge city-style growth.

Adjacent to I-95 between Wilmington and Newark, Delaware, the Christiana Mall opened in 1978. Beginning in the 1980s, after much of Wilmington’s industry disappeared, the unincorporated Christiana-Churchman’s Crossing area attracted firms such as Astra-Zeneca, Christiana Hospital, shopping centers University Plaza and Centre Point Plaza, hotels catering to business travelers, and a SEPTA regional rail station. North of downtown Wilmington, the Concord Mall opened in 1965 along US Route 202; by 2016, the US 202-US 1 axis, extending north into Talleyville, Delaware, and Chadds Ford and Concordville, Pennsylvania, contained office parks, shopping centers, and thousands of single-family homes. Reflecting the area’s commercial importance, in 2014 Chester County officials proposed a feasibility study for resuming rail service to central Philadelphia, which had been eliminated in the mid-1980s.

a color photograph of the front entrance of Parx Casino in Bensalem
The Bensalem-Levittown-Langhorne area has experienced edge city-style growth due to a number of popular attractions in the vicinity, including Sesame Place, the Oxford Valley Mall, and the Parx Casino, which opened in 2009. The area is supported by two SEPTA Regional Rail lines. (Photograph by G. Widman for VisitPhilly.com)

In the nearly three decades following Edge City’s publication, Garreau’s definition faced criticism. Edge cities had grown significantly, ultimately blurring the lines between them and older cities. Philadelphia experienced an economic resurgence in the 1990s and early 2000s that attracted “millennials” and “empty nesters,” while older towns such as Haddonfield, New Jersey; Ardmore, Pennsylvania; and Newark, Delaware, saw revitalization of their downtown areas. In 2016 Camden, long beleaguered by job loss and high crime, heralded a $1 billion waterfront development proposal by Liberty Property Trust. Urban planner Robert Lang (b.1959), charting the amount of office space in the region, reasoned in 2006 that while King of Prussia and Paoli, Pennsylvania, still retained edge city characteristics, other towns, including Christiana, Warminster, and Cherry Hill also witnessed high rates of occupational dispersal and outward growth. Along the I-295 corridor in South Jersey, the US 202-US 1 corridor in Chester County, Pennsylvania, and US Route13 in New Castle County, Delaware, clusters of office parks, retail stores, and housing appeared to form large conurbations, or what Lang termed “edgeless cities.” They not only competed with Greater Philadelphia’s traditional urban centers for population and revenue but refuted Garreau’s contention that edge cities were bound to outpace other suburban concentrations, even to the point of rendering them obsolete.

Stephen Nepa teaches history at Temple University, Moore College of Art and Design, and the Pennsylvania State University-Abington. A contributor to numerous books, journals, and documentary films, he is currently working on a project about urban ruins. He received his M.A. from the University of Nevada, Las Vegas, and his Ph.D. from Temple University. (Author information current at time of publication.)

Copyright 2017, Rutgers University


Victor Gruen

Library of Congress

Architect Victor Gruen is often called “the father of the shopping mall,” though ironically he envisioned his creation as a way to alleviate suburban sprawl and promote walking over automobiles. Gruen was born in Austria and his early experiences in downtown Vienna shaped his vision for vibrant walkable suburbs that discouraged automobile use. He emigrated to the United States in 1938. Gruen sought to urbanize America’s suburbs by providing a central mixed-use location for entertainment, dining, and shopping, likening his vision to a Greek agora, a public space used for markets or gatherings.

Gruen designed the Cherry Hill Mall in what was then Delaware Township, New Jersey. It was the state’s first fully enclosed climate-controlled shopping center and the largest in the world when it opened in 1961. It was an instant success, enough that the township was renamed Cherry Hill in the same year. Gruen’s design included a four-hundred-seat auditorium and community hall for civic functions and lined the corridors with aviaries of tropical birds, palm trees, and fountains. In its early years, the mall hosted art exhibits and other community events, but these functions were gradually discontinued. Rather than create a walkable downtown, the mall increased demand for automobile access. The Cherry Hill Mall had a role in draining commerce from long-established department stores in Camden and Philadelphia, contributing to their eventual closure.

Gruen disavowed his creation and continued to promote walking over automobiles throughout his life.

Willow Grove Park, 1914

Historical Society of Pennsylvania

Prior to its exponential growth in the latter half of the twentieth century, Willow Grove, Pennsylvania, was best known for its eponymous amusement park. Opened in 1896, Willow Grove Park was one of the original “trolley parks” built by streetcar companies to promote their lines. An estimated one million people visited Willow Grove Park in its first year of operation. In the early twentieth century, the park hosted daily free classical music performances by some of the era’s top composers, most famously John Phillips Sousa, whose band performed at Willow Grove annually. In the 1920s, the park switched its emphasis from musical performances to thrill rides.

Willow Grove experienced rapid suburbanization after World War II as new highways allowed residents to commute into Philadelphia and other suburbs for business. These highways also provided a convenient means to travel to more distant entertainment venues. The aging park closed permanently in 1975. In 1982, the Willow Grove Park Mall opened in its place. Only the park’s carousel was saved and incorporated into the mall. As with other edge cities, the presence of a major shopping center had a profound effect on Willow Grove, attracting businesses and residents to the town and increasing traffic and development. In the early twenty-first century, Willow Grove Park Mall was one of the busiest shopping centers in the region.

Aerial View of Levittown, Pennsylvania

Special Collections Research Center, Temple University Libraries

Developments known as Levittowns–manufactured suburbs of low-cost, mass-produced tract houses– drew middle-class residents from older industrial cities and suburbs after World War II. They grew to include their own commercial districts and shopping centers.

Parx Casino, Bensalem

Visit Philadelphia

The Bensalem-Levittown-Langhorne area has experienced edge city-style growth due to a number of popular attractions in the vicinity, including Sesame Place, the Oxford Valley Mall, and the Parx Casino, which opened in 2009. The area is supported by two SEPTA Regional Rail lines. (Photograph by G. Widman)

Highway Interchange, King of Prussia

Special Collections Research Center, Temple University Libraries

King of Prussia was one of the “edge cities” to rapidly develop after World War II. This tangle of turnpike off-ramps in 1954 underscores the automobile-centric nature of the development.

Downtown Chester, 1942

Special Collections Research Center, Temple University Libraries

The city of Chester, Pennsylvania, was once a thriving community, but loss of industry and subsequent migration of residents led to its decline after World War II. This photograph shows Chester in 1942, when its shipbuilding industry was at its peak.

Artist Conception of the Cherry Hill Mall, 1956

Special Collections Research Center, Temple University Libraries

The Cherry Hill Mall was one of the major factors in the rapid, edge city-style development of Cherry Hill, New Jersey. Cherry Hill became home to corporate parks, retail chains, suburban developments, and thoroughfares as people were enticed to live and work there. This image is an artist's rendering of the mall prior to its construction.

Campbell Soup Factory, Camden

Special Collections Research Center, Temple University Libraries

Older industrial cities like Camden, New Jersey, suffered with the rise of the edge city as middle-class residents relocated, leaving the city destitute because of a diminishing population and tax base. The Campbell Soup Company produced soup in Camden in some capacity from 1869 until 1990, when production was moved outside the Philadelphia area, though the company headquarters remained in Camden. The Camden factory with its iconic soup can water towers, seen here, was demolished in 1991.

Ardmore, Pennsylvania

Visit Philadelphia

Ardmore, Pennsylvania, located on the Main Line in Montgomery County, is an example of a city that has prospered on the periphery of Philadelphia, with a robust shopping and dining scene. These shops on Lancaster Avenue, Ardmore's main drag, are only blocks from Suburban Square, which opened in 1928 as one of the country's first shopping centers. (Photograph by R. Kennedy)

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Related Reading

Cammarota, Ann Marie. Pavements in the Garden: The Suburbanization of Southern New Jersey, adjacent to the City of Philadelphia, 1769 to the present. Madison, N.J.: Farleigh Dickinson University Press, 2001.

Garreau, Joel. Edge City: Life on the New Frontier. New York: Doubleday, 1991.

Lang, Robert E. Edgeless Cities: Exploring the Elusive Metropolis. Washington, D.C.: Brookings Institution, 2003.

Lang, Robert E., Thomas Sanchez, and Jennifer LeFurgy, “Beyond the Edgeless City: Office Geography in the New Metropolis,” National Center for Real Estate Research, 2006. ­­­

Mozingo, Louise A. Pastoral Capitalism: A History of Suburban Corporate Landscapes. Cambridge, Mass.: MIT Press, 2011.

Teaford, Jon C. The Metropolitan Revolution: The Rise of Post-Urban America. New York: Columbia University Press, 2006.

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