The twenty-first century is the first urban century in human history, the first time more people on the planet live in cities than don’t. Experts project that some 75 percent of the booming global population will be city dwellers by 2050. Dozens of new cities are springing up in Asia, their growth hastened by political unrest, climate change, and mass relocation programs that have cleared vast swaths of the Chinese countryside. Much of the growth in countries like India and Bangladesh is chaotic and badly planned. In many growing cities across the Global South there are serious shortages of water, sanitation, and housing, along with increasing air pollution. The United States has some of the same problems on a smaller scale, while here urban development is also being stimulated by growing numbers of university graduates and empty-nesters who are rejuvenating downtowns and rejecting suburbia, the culture of commuting, sprawl, and the automobile.

Not that suburbs have stopped growing, but since the late 1990s, the share of automobiles driven by people in their twenties in America has fallen from 20.8 percent to 13.7 percent. The number of nineteen-year-olds opting out of driver’s licenses has tripled since the 1970s from 8 to 23 percent. Electric, self-driving vehicles may soon revolutionize transportation and urban land use. Meanwhile, deindustrialization, plummeting crime rates, and increasing populations of singles and complex, nontraditional families have reshaped many formerly desolate urban neighborhoods.

People are moving downtown for jobs, but also for the pleasures and benefits of cultural exchange, walkable streets, parks, and public squares. Squares have defined urban living since the dawn of democracy, from which they are inseparable. The public square has always been synonymous with a society that acknowledges public life and a life in public, which is to say a society distinguishing the individual from the state. There were, strictly speaking, no public squares in ancient Egypt or India or Mesopotamia. There were courts outside temples and royal houses, and some wide processional streets.

By the sixth century BC, the agora in Athens was a civic center, and with the rise of democracy, became a center for democracy’s institutions, the heart of public life. In ancient Greek, the word “agora” is hard to translate. In Homer it could imply a “gathering” or “assembly”; by the time of Thucydides it had come to connote the public center of a city, the place around which the rest of the city was arranged, where business and politics were conducted in public—the place without which Greeks did not really regard a town or city as a town or city at all. Rather, such a place was, as the second-century writer Pausanias roughly put it, just a sorry assortment of houses and ancient shrines.

The agora announced the town as a polis. Agoras grew in significance during the Classical and Hellenistic years, physical expressions of civic order and life, with their temples and fishmongers and bankers at money-changing tables and merchants selling oil and wine and pottery. Stoas, or colonnades, surrounded the typical agora, and sometimes trees provided shade. People who didn’t like cities, and disliked democracy in its messiness, complained that agoras mixed religious and sacrilegious life, commerce, politics, and theater. But of course that was also their attraction and significance. The agora symbolized civil justice; it was organic, changeable, urbane. Even as government moved indoors and the agora evolved over time into the Roman forum, a grander, more formal place, the notion of the public square as the soul of urban life remained, for thousands of years, critical to the self-identity of the state.

I don’t think it’s coincidental that early in 2011 the Egyptian revolution centered around Tahrir Square, or that the Occupy Movement later that same year, partly inspired by the Arab Spring, expressed itself by taking over squares like Taksim in Istanbul, the Plaça de Catalunya in Barcelona, and Zuccotti Park in Lower Manhattan. And I don’t think it’s coincidental that the strangers who came together at places like Zuccotti and Taksim all formed pop-up towns on these sites, producing in miniature form (at least temporarily) what they imagined to be the outlines of a city, with distinct spaces designated for legal services, libraries, medical stations, media centers, kitchens serving free food, and general stores handing out free clothing.

Aristotle talked about an ideal polis that extended the distance of a herald’s cry, a civic space not so large that people could no longer communicate face-to-face. In Zuccotti Park, a contained space only a block long and wide, the police allowed protesters, who were prevented from using loudspeakers, to communicate by repeating phrase by phrase, like a mass game of telephone, what public speakers said, so that everyone, as it were, spoke in one voice. As in any healthy city or town, the occupants did not in fact all agree about goals and dreams or about how to bring about political and social change, even while they shared the same space; and without a sustained and organized structure of governance, their spontaneous occupation inevitably came apart, even before it was invaded and dispersed by the police. That said, for a time Zuccotti became a physical manifestation of democratic impulses and hopes embedded, since the days of the agora, in the very notion of a public square.

Seen whole, in all its variety and interconnectedness, urban health is expressed physically in a natural configuration of built forms across the city. The art of architecture requires not just making attractive buildings but providing citizens with generous, creative, open, inviting public spaces. And one of the basic truths of urban life turns out to be that there’s a nearly insatiable demand for such places. Under Mayor Michael Bloomberg’s administration, New York City inaugurated a program to convert streets across the five boroughs into plazas and squares.

Making Times Square into a pedestrian mall was the program’s main event. But the mayor’s office invited communities everywhere to suggest disused traffic triangles, parking lots, and other forlorn sites in far-flung areas that might also be reimagined. Dozens of new public spaces were proposed. The city carted in potted trees, benches, chairs, and tables, and voilà, new squares were created. Since then, they have not all been well maintained or supported by City Hall. But some of them made an immediate difference in reducing crime, boosting local commerce, and improving street life.

The big news was just how much people craved public squares. Madison Square Park, lately renovated and one of the loveliest parks in New York City, faces the Flatiron Building, where Fifth Avenue and Broadway cross. The two avenues created for years what was the widest and most unmanageable street crossing in Manhattan. The Bloomberg administration’s idea was to turn the middle of that street into a new public plaza. One day I ran across Michael Bierut, whose design firm, Pentagram, faces the site, and he told me he had thought the plaza was a crazy plan when he first heard about it. Who in the world would sit in the middle of the street, he wondered, when you had one of the most beautiful parks in the city right there?

“Was I wrong,” Michael recalled after the plaza was completed when I spoke with him for a column in The New York Times. Today, the place is full of people on nice days, its café tables and umbrellas scattered where trucks had rumbled down Broadway and Fifth Avenue. The new square instantly became one of the most successful public spaces in the city, with people toting prosciutto sandwiches out of Eataly, the nearby Italian food market, and Shake Shack burgers out of the park just to sit in the middle of traffic—because from there you can see the Flatiron Building one way and the Empire State Building the other, but also for the reason people gravitate to Trafalgar Square in London or the Piazza della Signoria in Florence as opposed to Hampstead Heath or the Boboli Gardens: to be in the middle of things.

As retreats, parks give us room to breathe and feel alone. Squares reaffirm our commonality, our shared sense of place, and our desire to be included. “It’s why we congregate near the kitchen at a dinner party instead of in the living room,” is how Andy Wiley-Schwartz, who directed the plaza program during the Bloomberg administration, described to me the attraction of the square. “That’s where you see people coming and going to the fridge to grab a beer and watch stuff happen.”

This impulse to watch stuff happen is universal. On another Times assignment, I visited a refugee camp in the southern West Bank called Fawwar. There, a Palestinian architect, Sandi Hilal, worked with residents of the camp to create a public square, something virtually unheard of in such places. For Palestinian refugees, the creation of any urban amenity, by implying normalcy and permanence, undermines their fundamental self-image, even after several generations have passed, as temporary occupants of the camps who preserve the right of return to Israel.

Moreover, in refugee camps, public and private do not really exist as they do elsewhere. There is, strictly speaking, no private property in the camps. Refugees do not own their homes. Streets are not municipal properties, as they are in cities, because refugees are not citizens of their host countries, and the camp is not really a city. The legal notion of a refugee camp, according to the United Nations, is a temporary site for displaced, stateless individuals, not a civic body.

So there is no municipality in Fawwar, just a UN relief agency whose focus is on emergency services. That’s what residents turn to when the lights go out or the garbage isn’t picked up, unless they want to deal with the problem themselves. Concepts like inside and outside are blurred in a place where there is no private property. A mother doesn’t always wear the veil in Fawwar, whether she’s at home or out on the street, because the whole place is, in a sense, her home; but she will put it on when she leaves the camp, because that is outside.

In other words, there is a powerful sense of community. And some years ago, Hilal—who then headed the Camp Improvement Unit in the West Bank for the United Nations Relief and Works Agency, along with her husband, Alessandro Petti, an Italian architect—began to talk with Fawwar residents about creating a public square. The residents, especially the men, were immediately suspicious, not just about normalizing the camp but about creating any space where men and women might come together in public. Fawwar was established in 1950. It’s under a quarter of a square mile, just south of Hebron, crammed with nearly seven thousand people, many the descendants of Palestinians who fled or were expelled from their homes in 1948. “I feel at home here,” said one middle-aged resident who was born and reared in the camp. “I want the right of return so I can decide for myself if I want to live here. It’s a matter of freedom, choosing where you live.”

Of course, this entire question is complicated by the refusal of many Arab states to take in Palestinian refugees, a refusal partly based on the claim of right of return. And I’ve heard that a survey taken decades ago suggested that some Palestinians would trade this right if they received substantial compensation. But in Fawwar the issue of the right of return clearly binds residents to the camp as a site of shared sacrifice and resistance. “It’s an architectural issue, in one respect,” is how Hilal put it. What she meant about it being an architectural issue was that identity in the West Bank (although not only there) is invariably tied up with notions of belonging and place and expressed through architecture, including public spaces like squares.

Hilal showed me around the square she’d designed. She said that pushback was initially fierce. “When we merely mentioned the word ‘plaza,’ people in the camp freaked out,” she remembered. But a counterargument gradually took hold, which entailed abandoning what Hilal called “the strategy of convincing the whole world of the refugees’ misery through their architectural misery.” Hilal focused on women, young and old. At first they didn’t want to oppose the men who were against it. But they feared, in such a conservative enclave, that if the square were built, men would simply take it over, and that if women did try to use it, they would feel too exposed in an open space. They longed for someplace to gather outdoors with a screen or enclosure.

So the challenge became: How could a space be made open—so that men, women, and children might be able to gather together—while also allowing the women some privacy? It was decided that a wall of varying height should surround the square, which was about 7,500 square feet. Three disused shelters from the 1950s were torn down. The wall created a kind of house without a roof, a space at once open and contained. The architects interviewed residents whose homes faced the site, and negotiated with each one separately about the appearance of the wall in front of their houses. What resulted is a dusty, L-shaped place, made of limestone and concrete, with several entrances, which has stirred debate in the camp about the position of women.

The square has given children a place to play other than crowded streets. Mothers who rarely felt free to leave their homes to socialize in public now meet there to talk and weave, selling what they make in the square, an enterprise that is entirely new in the community and that one of the mothers told me “gives us self-esteem and a sense of worth, like the men have.”

“For me,” another mother said, “the radical change is that men here now look at women in a public square as a normal phenomenon. I can bring my kids. I can meet my friends here. We are in our homes all the time. We need to get out. We want to be free. Here, in the public square, we feel free.”

Her remark put me in mind of a square that seemed to me just about perfect. Some years ago, I moved to Berlin with my wife and our two sons in order to start a newspaper column on cultural and social affairs across Europe and elsewhere. We settled into an apartment on a quiet street in the west and soon discovered Ludwigkirchplatz, a square, two blocks away. It unfolded at the rear of a neo-Gothic redbrick church from the 1890s, St. Ludwig’s, one of the few freestanding churches in Berlin. Several streets converged from different angles onto the square, which used to be the center of Wilmersdorf, a leafy cobblestoned quarter whose roots go back at least to the thirteenth century. George Grosz and Heinrich Mann lived nearby. Not long ago, Wilmersdorf was subsumed by Berlin administrators into a larger borough, Charlottenburg-Wilmersdorf, which includes the Ku’Damm—the Kurfürstendamm—West Berlin’s faded but undaunted version of Broadway or Paris’s Champs-Élysées, with its glossy auto dealerships and sprawling department stores.

Ludwigkirchplatz is off the beaten path. If several roads lead to it straight from the Ku’damm, they’re quiet, and you can still come upon the square as if upon a clearing in the woods. These are slumbering streets of stucco, stone, and concrete apartment blocks with funny little shops selling belly-dancing supplies, gay sex toys, Cuban cigars, and German wine. The square announces itself gradually, from a distance, with the sound of children playing and church bells.

It’s not quite an hourglass shape, paved in patterned bricks and shaded by rows of linden trees, with café tables spilling from bars facing the square. A sandy playground squats below the bellowing apse of the church. A raised semicircle of benches looks back toward the café tables and onto a pair of slightly tilted concrete ping-pong tables, which do a brisk business in warm weather. A plaza between the café tables and the ping-pong tables is the square’s main stage, where skateboarders vie with toddlers, dog walkers, young mothers pushing high-priced strollers, and Wilmersdorf widows, the last generation of war survivors, not unlike the Italian matrons whom I recall from my childhood in the Village, and similarly disapproving.

Someday we will lose all this and return home, I told myself whenever I arrived in that beautiful square under the towering church steeple and settled onto the benches beside the playground, where our children loved to play. The square was a home, drawing us daily as it did our neighbors. With the usual mix of sadness and pride, I watched our older son, just eight when we moved, grow up game by game, learning to play ping-pong on the lopsided tables; I watched our younger boy learn to walk in the sandbox near the swings. In December, when the square was silent and briefly taken over by Turkish immigrants selling Christmas trees, we lugged our tree to our apartment after a heavy German lunch in an old corner bar that had an especially lovely view of the slumbering playground and barren branches through steamfogged windows.

We declared spring’s arrival as soon as we could clear the snow from the ping-pong tables. Wilmersdorfers desperate for winter to end were there, too, wrapped in blankets, shivering at the outdoor café tables facing the square. If a polis is measured by the length of a herald’s cry, a parish extends the distance of a church bell’s ring, and the bells of St. Ludwig’s, while deafening in the square, filtered through the surrounding streets, binding the neighborhood together.

On our final day before moving back to New York, one of those cruelly perfect, sun-kissed summer Sundays in Berlin, my older son and I returned to the square for a few last games. The square was packed with newly arrived Russian émigrés and children carrying ice cream cones from the Italian gelateria facing the playground. “Everything is as it should be,” Nabokov once wrote. “Nothing will ever change, nobody will ever die.” The smell of fresh bread wafted from an organic bakery, just off the square, mixing with the perfume of lindens in bloom. Skateboards rattled over the stone plaza. The bells tolled for what seemed like an hour that afternoon. We played game after game, vainly hoping to slow time.

The perfect square, it turns out, is also a state of mind.

The Craving for Public Squares