Also: Montreal’s “remarkable” chance to build a new neighborhood, and who’s ready for super-long flights?

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What We’re Following

Drive time: In 1994, Cesare Marchetti, an Italian physicist, described an idea that has come to be known as the Marchetti Constant: Throughout history, urban dwellers—regardless of whether they walk, bike, ride, or drive—have been willing to travel for about an hour each day. Modern Atlanta may thus bear little resemblance to Ancient Greece or Medieval Paris, but residents of all three cities share this time-tested tendency to take on 30-minutes commutes.

(David Montgomery/CityLab)

The principle has profound implications for life in cities. New technologies have radically changed mobility over the centuries, and the footprints of cities have adapted as a result. But even as urban areas grew from two-mile-wide walking cities into eight-mile-wide streetcar cities into 40-mile-wide expressway cities, each new mode of transport eventually reaches its limit, putting strains on housing, jobs, and time. And many U.S. cities are reaching that breaking point now. Today on CityLab, Jonathan English takes us on a journey through 2,800 years of getting downtown: The One Weird Rule That Defines Urban Footprints

Andrew Small

More on CityLab

Montreal Gets a 'Remarkable' Chance to Build a New Neighborhood

A historic brewery on the St. Lawrence River will become a new mixed-use district, with a large share of subsidized and below-market-rate housing.

Tracey Lindeman

Who’s Ready for a 19-Hour Flight?

Qantas will test the world’s longest flights, from New York and London to Australian cities. An economist contemplates how we got here, and what success looks like.

Jay L. Zagorsky

We Heard You Like Maps So We Made You a Playlist

Songs about maps cross all genres and emotions. Got ideas for music to add to our playlist? Leave them in the comments or tag us on Twitter.

Gracie McKenzie

The Secret History of the Suburbs

We all know the stereotypes: Suburbia is dull, conformist, and about “keeping up with the Joneses.” But what about the suburbs of utopians and renegades?

Amanda Kolson Hurley

Are Planners Partly to Blame for Gentrification?

In his book Capital City, Samuel Stein contends that real-estate interests have co-opted urban planning and made planners complicit in gentrification.  

Tanner Howard

What We’re Reading

Inclusive cities start with safe streets (Curbed)

Mayors are harassed and threatened, but just how often? (Governing)

When a business improvement district pits pedestrian safety against homeless encampments (Washington City Paper)

More people are leaving New York City than any other U.S. city (Bloomberg)

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