Many streets in the oldest part of Quebec City are car-free much of the time. It is one of the most extensive car-free areas in North America. (CarfreeCities)

Each week, In Theory takes on a big idea in the news and explores it from a range of perspectives. This week, we’re talking about car-free cities. Need a primer? Catch up here.

J.H. Crawford is the author of “Carfree Cities” and “Carfree Design Manual,” and publisher of Carfree.com.

We must first remember that all cities were car-free little more than a century ago. Not all cities responded to the advent of automobiles with the same enthusiasm as the cities of the United States. In fact, some cities never did adopt the car. Venice was unwilling to destroy itself in order to build streets wide enough for cars, and therefore has never had them except in a sliver near the mainland. The same situation exists in the Medina of Fez, Morocco, and several other North African cities. These districts are usually the most vibrant parts of their cities.

Cars were never necessary in cities, and in many respects they worked against the fundamental purpose of cities: to bring many people together in a space where social, cultural and economic synergies could develop. Because cars require so much space for movement and parking, they work against this objective — they cause cities to expand in order to provide the land cars need. Removing cars from cities would help to improve the quality of urban life.

Transport modes have always exerted a strong influence on the basic arrangement of cities. The current form began to emerge in the 15th century, when the advent of horse-drawn carriages led to a demand for wide, straight streets. This requirement was adopted by Renaissance planners in most of Europe, and most urban plans of the past 500 years have straight streets that are relatively wide and corners that accommodate turning carriages. In many ways, this change was a harbinger of the automobile.

Transport, however, is not the only important use of streets. Streets are also our most important public social spaces. Most cities in Europe now acknowledge the terrible damage cars have done to this use, which is why cities all across Europe are discouraging automobile use in favor of walking, cycling and public transport. This is most clearly illustrated in Oslo, the first European capital to announce that its downtown core will soon be made car-free in order to reduce carbon emissions and improve air quality, as well as to improve conditions for pedestrians and cyclists.

Battery-powered and driverless cars do not affect this situation to any great degree. They still demand too much street space for their movement and use too much energy. The movement of significant numbers of cars through the streets will always damage streets’ social use, regardless of how quiet and safe the cars may be. Only when people can stop in the middle of the street to talk without fearing what may be bearing down on them will we have fully restored the social function of streets.

Good public transport coupled with fast, safe, pleasant walking and bicycling can easily meet the need for movement within our cities. It is true that buses and streetcars do intrude on the main streets to an appreciable degree, but many streets will be entirely free of this annoyance. In the ideal case, public transport systems are constructed underground. (Ideally, transport systems should never be elevated, because of the ugliness, intrusion and noise that that causes.) This will not be practical in many existing cities because of the cost, and some burden of street traffic will have to be endured.

A more serious objection to the car-free city is the movement of freight. When building a city, it is a simple matter to arrange delivery of shipping containers to the places they are needed without impinging on streets. In existing cities, freight delivery systems will have to be arranged on a case-by-case basis. Amsterdam could, with little difficulty, deliver freight using its canal network. Cities that adopt streetcars for passenger service can use the same infrastructure to deliver freight at night.

Removing vehicles from our streets would make urban life cheaper, safer, quieter and more pleasant. Repurposed parking spaces and, in some cases, travel lanes would provide ample land for walking and cycling, plus any essential street-running public services, such as light rail, trash collection and emergency services. The surplus land can be devoted to public purposes — imagine Manhattan with sidewalks 15 feet wider and room for sidewalk cafes.

Governments should welcome the change. The cost of supporting car traffic far exceeds the revenues generated by user fees. In Europe, it is the densest places that are first made car-free, and the pedestrian traffic generated by these places is the heaviest in the city. Stores and restaurants thrive in these areas.

I believe that the social benefits alone entirely justify the change. Imagine a busy city that is calm, quiet and beautiful. Venice, which comes closest to meeting this test, is visited by 20 million people a year, the most of any Italian city. Other car-free areas are immensely popular with residents and tourists alike. Shopkeepers have often opposed these changes, only to discover that their business improved once cars were gone.

It is true that a certain degree of convenience must be sacrificed for this change. However, the benefits are large, and we can expect significant improvements in public health as people return to more active modes of transport. The noise reduction alone is a significant public health benefit.

The car century was a seductive mistake. It’s time to move on.

Explore these other perspectives:

Randal O’Toole: Transit is dead. Let’s prepare for the next mobility revolution.

Shivani Radhakrishnan: How jaywalking became a crime

Jarrett Walker: Why cars and cities are a bad match.

Donald Shoup: How parking requirements hurt the poor

Aaron Renn: Self-driving cars will change more than just traffic. Here’s why.