Americans Don’t Know What Urban Collapse Really Looks Like

Neglect and inertia pose bigger threats to cities than the pandemic does.

A blurry image of the Manhattan skyline.
Olivier Coulange / Agence VU / Redux

If you’ve ever seen a picture of a lost city—maybe in the pages of National Geographic or in the first Tomb Raider movie—you were probably looking at the crumbling temples and immense, empty canals of Angkor, the former capital of the Khmer empire in present-day Cambodia. Thick tree roots have wrapped themselves around massive blocks of stone in its legendary palaces. Flowers grow from cracks in hundreds of ornate towers carved with the Buddha’s serene face. A thousand years ago, Angkor was among the world’s largest cities, with nearly 1 million residents. Today its iconic ruins are as famous as the city itself once was, attracting millions of tourists to Cambodia every year.

Though Angkor has always been widely known in Asia, Europeans became obsessed with it after the French explorer Henri Mouhot claimed he discovered the place in 1860. Mouhot described Angkor as a lost city, its past a fairy tale with no connection to present-day Cambodia. His vision of Angkor captured the Western imagination and popularized a myth about urban life cycles, in which cities follow a linear progression from humble origins to spectacular heights—and then collapse into obscurity. This myth continues to shape public understanding of urbanism a century and a half later. It haunts news stories about “pandemic flight” from Manhattan and San Francisco, and it is the unspoken subtext of anxious questions about whether Detroit and New Orleans, cities battered by economic or ecological catastrophes, are at risk of dying.

Having witnessed a decline in U.S. cities’ fortunes over the past year, many American commentators are predicting the dissolution of entire communities too eagerly. Having spent the past several years researching a book about ancient abandoned cities, I’ve come to realize that urban collapse is a modern-day version of an apocalypse prophecy: It’s always lurking just around the corner, seductive and terrifying, but it never quite happens. Lost-city anxieties, like the ones aroused by the pandemic, result from a misunderstanding of what causes cities to decline. Pandemics, invasions, and other major calamities are not the usual culprits in urban abandonment. Instead, what kills cities is a long period in which their leaders fail to reckon honestly with ongoing, everyday problems—how workers are treated, whether infrastructure is repaired. Unsustainable, unresponsive governance in the face of long-term challenges may not look like a world-historical problem, but it’s the real threat that cities face.

In recent decades, archaeologists and geologists have reanalyzed the evidence about what happened at Angkor. What they found is the truth behind the lost-city myth: Great cities are rarely snuffed out in an instant, nor do they “collapse.” Instead, they transform.

For centuries, Angkor was the capital of the powerful Khmer empire, which spanned today’s Cambodia, Laos, Thailand, Myanmar, Vietnam, and parts of China. The empire’s boundaries grew and shrank dramatically from the 800s to the 1600s, and Angkor’s residents changed as successive waves of immigrants came to settle there after new conquests. At the nexus of two fierce monsoon weather patterns, it wasn’t an easy place to live. But Khmer kings ordered their laborers—many of them enslaved—to build enormous reservoirs and canals to prevent Angkor from flooding in the rainy season and desiccating in the dry one. Angkor was a marvel of hydrological engineering, and renowned across Asia for its beautiful architecture.

Then, according to what became the dominant story, Angkor fell abruptly in 1431 after it was sacked by the neighboring Ayutthaya kingdom, in today’s Thailand. Many historical accounts represent this date as a hard end to the great city, giving the misimpression that hundreds of thousands of people dropped everything and fled by 1432, leaving the temples to be consumed by trees.

In reality, as the archaeologists Alison Carter, Piphal Heng, and their colleagues argued in a recent paper, the city continued to thrive. What happened in 1431 was that the Khmer royal family fled south to Phnom Penh, where it remains today. As for all the nonroyals? They continued to live at Angkor, repaired its ailing water infrastructure, recycled stones from temples into new structures, and planted farms where high-density housing once was. Life probably improved for many people who otherwise would have spent part of the year as debt slaves in the service of nobles. In the 16th century, King Ang Chan even tried to revitalize what remained of the city’s downtown with new wall paintings and a luxurious stupa, or family shrine. Eventually the population trickled away, but that took centuries.

Angkorian culture did not disappear, as Mouhot claimed. Its influence is still widely felt in Theravada Buddhism, a unique strand of Buddhism, popularized by Khmer King Jayavarman VII, that is practiced by most Cambodians. When Mouhot showed up in 1860, monks were still living in the temple enclosures at Angkor Wat and Angkor Thom; they received pilgrims who came from all over Asia to honor ancestral traditions. And this is still the case. Angkor is no longer a major urban capital, but it’s still a key part of Cambodian life through religion and tourism. Throughout its many changes, the city was never lost.

This is an important reality check for people fretting over the imminent demise of, say, Detroit or Los Angeles in the aftermath of economic and natural disasters. Detroit’s rich and famous may have fled like the Khmer royals splitting from Angkor in 1431. But the city’s revitalization also sounds a lot like Angkor’s, with neighborhoods setting up urban farms and rebuilding abandoned structures. Obviously the parallel is not perfect—no real-estate companies bought up land in Angkor for redevelopment—but we see the same pattern of locals repurposing older parts of the landscape. Detroit could continue thriving for centuries, revising its 20th-century land-use patterns to suit new populations.

Angkor also has something in common with Los Angeles, Houston, and other cities facing imminent threats from fires and floods as climate change worsens. In the late 14th and early 15th centuries, Angkor was hit by several droughts and intense monsoon seasons in a row. The weather extremes upended daily life. But the real blow came when civic leaders bungled maintenance of the city’s water system in response to the climate threats—leading to catastrophic floods, silt-clogged canals, and crop failures. People began to move away from the city in the 14th century when it became clear that much-needed infrastructure repairs were never going to happen.

This slow-motion catastrophe—a combination of natural disaster and political indifference—was far more important to the city’s transformation than the Ayutthaya invasion. And it stands as a warning to many cities in the U.S. Without a coherent response from local government, cities lashed by climate change will gradually lose their populations. The demise won’t be spectacular, even if the storms are monstrous. Instead, people will leave in dribs and drabs, and the exodus could take generations.

Yet fantasy writers and urban pessimists alike continue to embrace the lost-city trope, in which a dazzling metropolis evaporates overnight, never to be heard from again. This notion’s persistence is not entirely Mouhot’s fault. His stories about Angkor were shaped by entrenched colonial ideas about how Cambodia and other Southeast Asian nations were uncivilized and couldn’t have produced the vast, wealthy urban network that Europeans saw in the ruins of the Khmer empire. Lurking in the deep background of lost-city stories is an imperialist fantasy that there are “winner” civilizations, worthy of celebration, and “loser” civilizations, destined to be forgotten. The reality is much more ambiguous.

Perhaps the fear of becoming one of those “loser” civilizations helps explain the current anxieties about how the coronavirus pandemic is causing people to flee San Francisco. When our only models for urban transformation come from lost-city tales, it’s hard to wrap our heads around the idea that some people will leave, some will stay, and still others will work to make the city more livable for the next generation. Imagining an apocalypse against which a city is helpless may be psychologically easier than doing the hard work, over years or decades, to bring about slow but wrenching change. Nevertheless, urbanites must be prepared for a gradual, bumpy transformation—at least, if they hope to base their futures on lessons from history, rather than on myths inherited from colonizers, travel literature, and action movies.