In a memorable scene in “The Big Short,” the Oscar-nominated 2015 movie about the financial crisis, a real estate agent shows the main characters around a desolate Florida subdivision. She insists that the market is just in a lull as they drive past rows and rows of vacant homes.

But it wasn’t just a lull. It was the housing bubble bursting, and that emptiness was replicated in communities around the world as people lost their homes and developers' projects went bust.

One of the worst cases was in Spain, where there were more than 3 million unoccupied homes in 2014. Half-finished developments still dot the landscape.

Christopher Marcinkoski Northwestern area of Ciudad Valdeluz, known as the Miraflores district, in 2014.

They’re the subject of The City That Never Was, a book published in January by Christopher Marcinkoski that investigates what he calls “speculative urbanization." He uses the term to describe what happens when public and private groups embark on large development projects for an economic boost rather than actual need, and shows the devastating consequences.

In the early 2000s, there was a huge construction boom as provinces across Spain raised entire new cities, airports and massive infrastructure projects.

PNOA The El Cañaveral development, shown from above in 2002 and 2012, is located in central Spain.

"You could find, very easily, villages of 300 people that were undertaking expansions that would double and triple the housing stock," Marcinkoski said.

Marcinkoski, an assistant professor of landscape architecture at the University of Pennsylvania, noticed the pattern when he visited Spain in 2010.

"The amount of housing that was produced was still beyond the amount of any [population] projections," he said. "I realized it was more than just one city or a localized condition, but rather was something pervasive across almost the entirety of the country."

Christopher Marcinkoski Overview of Ciudad Valdeluz, looking to the west-southwest, in 2014. Meant as a community for middle-income families who wanted more space than was availably in nearby Madrid, the development was never finished.

One dramatic example of speculative urbanization is Ciudad Valdeluz, about 40 miles from the capital city of Madrid. Construction began in 2006. It was intended to hold 30,000 residents, and included plans for a train station that would link them to the capital, as well as parks, sports centers and schools.

Many of the plans never materialized. Fewer than 3,000 people now live there, without the basic services or easy commute to job centers that they were expecting.

"The feedback that we got was a sense of being stuck, that they were sold a false bill of goods," Marcinkoski said. "That sense of isolation, that sense of not quite getting what we were sold, was a pretty pervasive thing that we heard.

Ricardo Espinosa Large and incomplete public spaces throughout the Ensanche de Vallecas development near Madrid, shown in 2014, exacerbates the sense of emptiness and abandonment.

"They are pretty surreal environments," he continued. “The absence of people helps you understand the scale of the places, even if they’re not fully built out. You can see the markings of the roadways or the block structures sort of stretching out into the distance, and you recognize how big these things were intended to be, and that sort of scale makes it more obvious how irrational they were in their undertaking."

Spain also overextended itself on infrastructure projects like airports. Eight new ones were built in the country between 1990s and 2010, and 21 more were expanded, Marcinkoski wrote. Several have ceased operations and others offer just a few flights.

Christopher Marcinkoski An incomplete pedestrian connector between a terminal at Aeropuerto Central Ciudad Real and an unbuilt high-speed train station, 2012.

Similarly, millions of euros were poured into constructing new roads. Many were never finished.

"A lot of the infrastructural building ended up being more about nation building than it was about long-term, sustainable planning and building logic, ... and that led, in my mind, a great deal to the housing glut that was produced," Marcinkoski said.

Christopher Marcinkoski An incomplete connection between MP-203 and R-3, two roads south of Mejorada del Campo in Spain, 2014.

Marcinkoski spreads the blame for Spain’s speculative development. But The City That Never Was is aimed at professionals in his own field. He argues that designers and planners are "complicit" in "the creation of these failures."

He said designers should acknowledge and plan for the fact that large-scale urbanization projects are volatile and often don't end up looking how they were originally envisioned. He suggested modular designs that could be adjusted as developments are built and occupied.

Ricardo Espinosa Shown here in 2014, the billboard advertising Los Berrocales was present throughout the economic downturn.

"When you look historically, we should know that these speculative bubbles are going to continue to occur,” Marcinkoski said. “Given that inevitability, perhaps we could think differently about how we plan, design and implement these projects."

It’s a pressing issue to Marcinkoski, because the financial crisis didn't end speculative urbanization, particularly in rapidly developing countries like China. He’s now looking at the phenomenon in Africa's growing cities.

Christopher Marcinkoski The nearly-empty El Cañaveral development near Madrid, seen from above in 2014. The strip of housing in the foreground is La Cañada Real Galiana, said to be Europe's largest shantytown. Several years ago, Madrid demolished parts of the informal settlement.

"A lot of the mistakes that we have seen are being replicated” in Africa, Marcinkoski said. “There’s an opportunity there to think about alternative ways where upgrades to settlements and infrastructure could be undertaken in a more rational and more adjustable manner, and not so focused on just the image of modernity, but actually the reality of need."

Kate Abbey-Lambertz covers sustainable cities, housing and inequality. Tips? Feedback? Send an email or follow her on Twitter.

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