On April 27, at a Bloomberg CityLab conference organized by Bloomberg Philanthropies and the Aspen Institute in Madrid, dozens of mayors gathered in a closed-door forum to hear two urban visionaries present their most hard-won lessons.

One was Anne Hidalgo — the former mayor of Paris, who spent twelve years transforming one of the world's most car-dependent capital cities into something resembling a city designed for the people who live in it. The other was Norman Foster — the British architect whose work spans the Reichstag in Berlin, 30 St Mary Axe in London, and a master’s programme on sustainable cities that operates across three continents from his foundation in Madrid.

They were asked to share their most important lessons on designing public space. They gave, independently, the same answer.

Get rid of the cars.

Hidalgo spent twelve years in office doing exactly that. She removed 70,000 parking spaces. She pedestrianized the Seine riverbanks — a stretch that once channeled 43,000 cars daily past the Louvre and the Pont Neuf, filling the river corridor with noise and exhaust. She added 550 kilometres of bike lanes over a decade, reaching 1,400 kilometres total by March 2026. She launched “Rues aux Écoles” — permanently blocking traffic on 100 streets around public schools. She swam in the Seine during the 2024 Olympics, having spent years campaigning to make the river clean enough to enter. Paris now surpasses London and Madrid in air quality.

Her legacy is contested. Traffic jams rose 4% since 2015 as cars concentrated on remaining roads. Bus use dropped 31% between 2018 and 2024. Suburbanites who depend on cars to reach the city feel the agenda was built for younger, wealthier, more mobile Parisians. Her successor, Emmanuel Grégoire, will inherit both the transformation and its discontents.

But in the mayoral forum in Madrid, what Hidalgo and Foster agreed on was not the politics. It was the principle. Cities were not designed to move cars. They were designed to house people. The street is not a throughput mechanism. It is a public good — the original public good, before parking replaced plazas and traffic lanes replaced civic space.

Foster's Norman Foster Institute now runs a Master's Programme on Sustainable Cities in Madrid, its provost Edgar Pieterse, alongside MIT’s Kent Larson. The programme teaches architects, data scientists, and urban planners to build compact, walkable, inclusive cities based on evidence rather than fashion.

The conference was attended by mayors from cities across the world. The message they heard was the same one Hidalgo had been implementing for twelve years in Paris, and the same one Foster has been teaching for decades in his buildings and his school:

The city begins when you decide the car does not come first.

(Sources: Bloomberg CityLab / Bloomberg Graphics Paris Transformed / CNN Paris Hidalgo / Norman Foster Institute — April–May 2026)

Tokyo 🇯🇵 — Tokyo never made Paris's mistake of designing itself primarily around the car. The city's extraordinary transit system — carrying more passengers daily than any other urban rail network on earth — was built as the primary mobility infrastructure, with car ownership and driving treated as supplementary rather than central. What Tokyo has, which Paris is building toward, is a city whose spatial logic does not require the removal of cars because it was never organized around them. The lesson Hidalgo and Foster's students should take from Tokyo is not a technique. It is a sequence: build the public transport first, comprehensively, before the city's spatial patterns calcify around automobile dependency. Paris is retrofitting. Tokyo started from a different premise. The retrofit takes twelve years and political courage. The alternative is harder.

Dallas 🇺🇸 — Dallas is the argument on the other side — the city that fully committed to the automobile and built itself around it. In North Texas, the car is not a convenience. It is an infrastructure assumption embedded in zoning, in land use, in the distances between things, in the absence of meaningful public transit at scale. The Bloomberg CityLab conference's message — get rid of the cars, the city comes back to life — would land in Dallas as a proposal to rebuild the city's entire operating logic from scratch. And yet: Dallas is hosting nine World Cup matches in June 2026, drawing millions of international visitors who will arrive at DFW airport and need to get to AT&T Stadium. The city’s car dependency will be visible to the world in a new way. Norman Foster has designed airports, stadiums, and transit systems. If he were advising Dallas in the way he advised Paris, the first question would be: what do people do when they arrive?

San Francisco 🇺🇸 — San Francisco has been trying to implement Hidalgo's strategy for years and has produced, so far, a more contested version of her results. The Embarcadero Freeway was demolished after the 1989 earthquake — the same political logic as Cheonggyecheon and the Seine riverbanks: remove the road, restore the civic space. The Valencia Street protected bike lane, the Slow Streets programme, the Market Street car ban — these are the San Francisco version of Hidalgo's agenda. But San Francisco has not managed Paris’s political consistency. The car bans come and go with administrations. The parking politics reverse. The bike lane gets removed when a business complains. What Hidalgo demonstrated in twelve years is not just a design principle but a governance principle: transformation requires sustained political will across multiple budget cycles and multiple elections. San Francisco has the design conviction. It has not yet built the political infrastructure to hold it.