Clive Thompson:

A 2011 study at the University of California-Berkeley found that the United States has somewhere close to a billion parking spots. Since there are only 253 million passenger cars and light trucks in the country, that means we have roughly four times more parking spaces than vehicles. If you totaled up all the area devoted to parking, it’d be roughly 6,500 square miles, bigger than Connecticut.
 Social critics often complain that the interstate highway system deformed the United States by encouraging sprawl. But the metastasizing of parking has had equally profound effects. On an aesthetic level, it makes cities grimly ugly. Economically, it is expensive to build. A study by the Sightline Institute found that at least 15 percent of the price of rent in Seattle stemmed from developers’ cost of building parking.
 Those costs are passed on to tenants whether they own a car or not (on top of any per space fee the landlord charges)—padding rent by an average of $246 a month in Seattle and $225 nationwide.
 And worst of all may be the emissions that parking causes. Studies have found that anywhere from about 30 to 60 percent of the cars you see driving around a downtown core are just circling, looking for an open space to claim. (An IBM survey found that worldwide, urban drivers spend an average of 20 minutes per trip looking for parking.) When Donald Shoup, an urban-planning professor at the University of California-Los Angeles, examined just one small business area near his university—Westwood Village—he found that “cruising” for parking, as he dubs it, burns 47,000 gallons of gas and generates 730 tons of carbon dioxide a year. What’s more, all that asphalt traps heat and raises the temperature of cities during the summer. Environmentally, aesthetically, and economically, parking is a mess.
 If you totaled up all the land devoted to parking, it’d be roughly 6,500 square miles, bigger than Connecticut.
 But for the first time in history, urban experts are excited about parking—because they can see the end in sight.
 We are, they say, on the cusp of a new era, when cities can begin dramatically reducing the amount of parking spaces they offer. This shift is being driven by a one-two punch of social and technological change. On the social side, people are increasingly opting to live in urban centers, where they don’t need—or want—to own a car. They’re ride-sharing or using public transit instead.
 And technologically, we’re seeing the rapid emergence of self-driving cars. Google’s models have traveled more than a million miles with almost no accidents, and experts expect that fully autonomous vehicles will hit the consumer market as early as a decade from now. Indeed, car technology is advancing so rapidly that it’s causing legitimate economic concerns. Already, companies like Uber and Lyft are under fire for treating drivers as independent contractors, with far fewer rights and benefits than employees (see “Road Warrior”). And that disruption is nothing compared with what will happen once cars can drive themselves; millions of taxi, delivery, and long-haul trucking jobs that traditionally have gone to new immigrants and low-education workers could vanish in a few years. Labor activists and economists are understandably alarmed at the prospect.
 But at the level of urban design and the environment, self-driving cars could produce huge benefits. After all, if cars can drive themselves, fleets of them could scurry around picking people up and dropping them off, working with sleek, robotic efficiency. With perfect computerized knowledge of where potential riders were, they could pick up several people heading the same way, optimizing ride-sharing on the fly. One study suggests a single self-driving car could replace up to 12 regular vehicles. Indeed, many urbanists predict that fleets of robocars could become so reliable that many, many people would choose not to own automobiles, causing the amount of parking needed to drop through the floor.