What is a city for? Ever since cities first emerged thousands of years ago, they have been places where families could congregate and flourish. The family hearth formed the core of the ancient Greek and Roman city, observed the nineteenth-century French historian Fustel de Coulanges. Family was likewise the foundation of the great ancient cities of China and the Middle East. As for modern European cities, the historian Philippe Ariès argued that the contemporary “concept of the family” itself originated in the urbanizing northern Europe shown in Rembrandt’s paintings of bourgeois life. Another historian, Simon Schama, described the seventeenth-century Dutch city as “the Republic of Children.” European immigrants carried the institution of the family-oriented city across the Atlantic to America. In the American city until the 1950s, urbanist Sam Bass Warner observed, the “basic custom” was “commitment to familialism.”

But more recently, we have embarked on an experiment to rid our cities of children. In the 1960s, sociologist Herbert Gans identified a growing chasm between family-oriented suburbanites and people who favored city life—“the rich, the poor, the non-white as well as the unmarried and childless middle class.” Families abandoned cities for the suburbs, driven away by policies that failed to keep streets safe, allowed decent schools to decline, and made living spaces unaffordable. Even the partial rebirth of American cities since then hasn’t been enough to lure families back. The much-ballyhooed and self-celebrating “creative class”—a demographic group that includes not only single professionals but also well-heeled childless couples, empty nesters, and college students—occupies much of the urban space once filled by families. Increasingly, our great American cities, from New York and Chicago to Los Angeles and Seattle, are evolving into playgrounds for the rich, traps for the poor, and way stations for the ambitious young en route eventually to less congested places. The middle-class family has been pushed to the margins, breaking dramatically with urban history. The development raises at least two important questions: Are cities without children sustainable? And are they desirable?

Best-selling urban booster Richard Florida, a pied piper for today’s city developers and planners, barely mentions families in his books, which focus instead on younger, primarily single populations. Eric Klinenberg, a New York University professor and author of the widely touted Going Solo, celebrates the fact that “cities create the conditions that make living alone a more social experience.” But perhaps the most cogent formulation of the post-family city comes from the sociologists Richard Lloyd and Terry Nichols Clark, who see the city, and particularly the urban core, as an “entertainment machine.” In their view, city residents “can experience their own urban location as if tourists, emphasizing aesthetic concerns.” Schools, churches, and neighborhood associations no longer form the city’s foundation. Instead, the city revolves around recreation, arts, culture, and restaurants—a system built for the newly liberated individual.

Demographic trends seem to bear out this vision. Over the past two decades, the percentage of families that have children has fallen in most of the country, but nowhere more dramatically than in our largest, densest urban areas. In cities with populations greater than 500,000, the population of children aged 14 and younger actually declined between 2000 and 2010, according to U.S. Census data, with New York, Chicago, Los Angeles, and Detroit experiencing the largest numerical drop. Many urban school districts—such as Chicago, which has 145,000 fewer school-age children than it had a decade ago—have seen enrollments plummet and are busily closing schools. The 14-and-younger population increased in only about one-third of all census-designated places, with the greatest rate of growth occurring in smaller urban areas with fewer than 250,000 residents.

Consider, too, the generation of Americans between the ages of 25 and 34 in 2000. By 2010, the core cities of the country’s 51 most populous metropolitan areas had lost, on average, 15 percent of that cohort, many of whom surely married and started having children during that period. While it’s not possible to determine where they went, note that suburbs saw an average 14 percent gain in that population during the same period.

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Of course, not all sections of our largest cities are equally bereft of children. Of Los Angeles County census tracts where less than 10 percent of the population was 14 and younger in 2010, a significant number were located downtown and along the coast. These are mostly high-density areas where housing is expensive. You’ll find a considerably higher proportion of children under 14 in low-income parts of South and East Los Angeles, and also in middle-class neighborhoods in the heart of the San Gabriel and San Fernando Valleys.

Opinion polls confirm the impulse behind the child exodus. For example, in a recent survey for the Manhattan Institute by Zogby Analytics, 58 percent of people with children under 17 said that they would consider leaving New York City for better opportunities elsewhere; only 38 percent of those without children agreed. Part of the reason is surely the city’s density and cost, which make family life difficult. In Manhattan, where the average rent approaches $4,000 a month, it’s no surprise that families are waning.

A more family-friendly city remains possible. The Brooklyn community of Flatbush—like Staten Island, Queens, and eastern portions of Brooklyn—was built in the first half of the twentieth century to appeal to families fleeing the congestion of New York’s core. Just as the suburbs do now, these new settlements revolted many urbanists, such as Lewis Mumford, who complained in 1921 that the “dissolute landscape” was “a no-man’s land which was neither town nor country.” But Flatbush’s tree-lined neighborhoods, such as Kensington and Ditmas Park, may be the city’s best hope for retaining middle-class families. These areas still have many single-family homes and low-rise apartments. And Cortelyou Road, a main drag in Ditmas Park, brims with family-friendly restaurants and shops, though it was fairly desolate just a decade ago. Young families are enthusiastic about the neighborhood. “It’s an amazing place,” says Kari Browne, co-owner of the Lark café on nearby Church Avenue. “But the key concern is: Can you afford to stay?”

For many young families living in New York’s outer boroughs, the availability of space, particularly backyards, is deeply important. “The cost of space is the biggest issue in Brooklyn,” says resident Michael Milch, whose wife attends dental school at NYU. “The issue becomes: Can you get some personal green space?” Obviously, people who settle here are willing to make do with less space than those who, say, move to a far-flung exurb in Putnam County. But all are seeking space in communities more amenable to family life than are the contemporary city cores. Heightened family demand may be helping send housing prices steadily upward in New York’s boroughs, as young couples move from Manhattan to less dense neighborhoods. Jason Walker, a 45-year-old father of two, left Washington, D.C. (which may have the highest percentage of childless households in the nation), for Ditmas Park to escape “a culture dominated by childless people leery of the existence of kids.” The Walkers live in a two-bedroom apartment but are looking for a house in the area.

Such opportunities exist elsewhere in America, too, in places where detached single-family homes—the preferred housing of 80 percent of American adults, according to a National Association of Realtors survey in 2011—are often just a short walk or ride from the urban core. With its broad streets and massive shopping centers, the California city of Irvine may lack the inner-ring charms of Flatbush. But families are drawn to Irvine’s amenities—especially its schools. “You really have to worry about the schools in New York,” says Walker, whose children are six and eight. “If you have to go to private schools, this makes it a struggle to stay here.” In Irvine, by contrast, “everything stems from education,” says resident Eveleen Liu. “The city draws people who are impassioned about their kids and their school. Everyone volunteers. It’s the glue that holds this place together.” Schools are particularly crucial in attracting Asians, now the country’s fastest-growing immigrant group. Safety is another big draw: Irvine consistently rates among the safest American cities with more than 100,000 residents.

Families are also deeply attracted to open space. The great Frederick Law Olmsted–designed New York parks, including Prospect Park in Flatbush, are enormous assets for families without backyards. Irvine may lack stunning urban architecture and glorious cathedrals, but it has a magnificent park system that gives residents ideal settings for recreation, exercise, and family gatherings. “It’s an environment that is clean and nice and open to everyone,” says Veronika Kim, a mother of three and an apartment tenant in Woodbury, an Irvine neighborhood. “You can walk there with the kids and let them play. Even if you rent, you don’t feel like an outsider.” The parks are good not only for kids but for adults—for example, the members of the Woodbury Woodies, who play softball every week against teams from other neighborhoods. “There’s a deep sense of community here,” says Woody regular Julian Forniss. “Softball is part of that.” On the site of a former Marine Corps base, Irvine and Orange County are developing a “Great Park” that will be twice the size of New York’s 840-acre Central Park.

Other family-friendly cities have embarked on ambitious park and open-space projects as well. In Raleigh, North Carolina, the nearly completed $30 million Neuse River Greenway Trail cuts through 28 miles of forest. Houston’s $480 million Bayou Greenways project will eventually add some 4,000 acres of green space across the city, from the downtown to the outer suburbs, including 300 miles of continuous hiking and bike trails. Houston’s rival, Dallas, is planning a vast 6,000-acre park.

What families need is more affordable urban neighborhoods with decent schools, safe streets, adequate parks—and more housing space. As New York University’s Shlomo Angel points out, virtually all major cities worldwide are growing outward more than inward—and becoming less dense in the process—because density drives families away from urban cores and toward less dense peripheries. The lesson is clear: if cities want families, they should promote a mixture of density options.

The solution is not to wage war on suburbia, as urbanists have been doing for years. Following the notions that Jane Jacobs advanced a half-century ago, contemporary urbanists argue that high density creates a stronger sense of community. (Jacobs once opined that raising children in the suburbs had to be difficult, somehow overlooking how families were flocking to those suburbs.) But that contention isn’t self-evident. The University of California’s Jan Brueckner and Ann Largey conducted 15,000 interviews across the country and found that for every 10 percent drop in population density, the likelihood of someone’s talking to his neighbor once a week went up 10 percent, regardless of race, income, education, marital status, or age.

In California, particularly, state and local officials push policies that favor the development of apartments over single-family houses and town houses. But by trying to cram people into higher-density space, planners inadvertently help push up prices for the existing stock of family-friendly homes. Such policies have already been practiced for decades in the United Kingdom, making even provincial cities increasingly unaffordable, as British social commentator James Heartfield notes. London itself is among the least affordable cities in the world. Even middle-class residents have been known to live in garages, converted bathrooms, and garden sheds.

A city that continues to be high-density and high-cost hasn’t necessarily signed its own death warrant. Manhattan, parts of Brooklyn, and much of San Francisco, Seattle, Boston, and other amenity-rich cities—what Tulane University geographer Richard Campanella calls “kiddie deserts”—continue to flourish. But other cities, such as Detroit, Cleveland, and Buffalo, can’t attract the same interest from young hipsters and the rich and are consequently less capable of withstanding the effects of family flight to the suburbs. Even in the most affluent cities, the dearth of families reinforces public policies incompatible with children, argues the Austrian demographer Wolfgang Lutz. For example, fewer middle-class families means less political pressure to reform education or support for tougher law enforcement.

Ultimately, everything boils down to what purpose a city should serve. History has shown that rapid declines in childbearing—whether in ancient Rome, seventeenth-century Venice, or modern-day Tokyo—correlate with an erosion of cultural and economic vitality. The post-family city appeals only to a certain segment of the population, one that, however affluent, cannot ensure a prosperous future on its own. If cities want to nurture the next generation of urbanites and keep more of their younger adults, they will have to find a way to welcome back families, which have sustained cities for millennia and given the urban experience much of its humanity.

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