Detroit Mayor Mike Duggan says he can see three parking garages along the riverfront from his office window. Like any mayor, he’s optimistic about his city’s future — despite Detroit’s well-known problems — and he sees growth in terms of more apartment and office buildings. But the capital of the American car has already reached peak parking garage.

Reasons for the decline of the parking garage are many, and the rise of ride-sharing services like Uber and Lyft are top-of-mind, but the autonomous car is what will ultimately make them extinct.

Duggan explains why:

“If self-driving vehicles are really close, it may not be that people are going drive a car and store it for eight hours in a structure; it may be that the self-driving car takes you to work, goes back home, and does errands with your spouse,” Duggan said. He was part of a mayoral panel hosted by Ford called “City of Tomorrow” at the North American International Auto Show in Detroit.

Also, office parking garages that fill up during the workday are often different from garages that are built for entertainment; those only fill up during concerts, conventions, and professional sports. (An interesting side-effect of less-busy garages is that beer sales shoot up as more use Uber).

With self-driving cars in our short-term future, the long-term forecast doesn’t look good for objectively ugly, concrete garages that fill American cities.

A parking garage in Denver. It sure looks like something! Wikimedia Commons

“If a parking structure has a 50-year life expectancy,” Duggan said, “we should think about building smaller ones, at the very least.”

Duggan was joined by Atlanta Mayor Kasim Reed, Chicago Mayor Rahm Emanuel, and Columbus, Ohio, Mayor Andrew Ginther. Each of the four said they expect autonomous cars in their cities within five to seven years.

In Atlanta — a city with a well-documented “parking addiction” — leaders agreed last year to a $6 billion expansion of Hartsfield-Jackson International Airport, and yes, a parking garage was involved. The deal was crucial because it included a 20-year lease with Delta that kept the airline’s headquarters (and jobs) there. Reed said that in the original proposal was a $1.5 billion parking deck. The Atlanta mayor said the city chose a smaller parking structure after discussing autonomous cars.

“We trimmed the cost of the parking deck from $1.5 billion to about $800 million, and it helped us get a $6 billion deal done,” Reed said.

Reed sees self-driving vehicles as a five to seven-year issue, not a ten to fifteen-year one.

“I don’t buy this ten-year, fifteen-year stuff,” he said, noting that the industry is going over the regulatory and liability hurdles now. (In September, the Department of Transportation issued its Federal policy for automated vehicles.)

The question is now, who will mourn the parking garage?

Watch the full panel below for more, including what the mayors think about bike lanes, public transit, and Donald Trump: