Coolness was invented by the city. Or to be more precise, the term “cool” first got hot in the back alleys and nightclubs that gave us jazz. It supplanted superlatives like swell and the bee’s knees and held steady amid the rise and fall of groovy, phat, sick, sweet and countless others. Despite the staying power and urban roots of coolness, what makes a city cool has remained an enigma.

A new paper by Florian Kock, an associate professor of Marketing and Tourism at Copenhagen Business School, claims to have cracked the code. Using qualitative and quantitative research, including interviews with American and German travellers, Kock determined that the coolest cities are authentic, rebellious, original and vibrant in varying degrees.

Paris rates high in authenticity, but low on rebelliousness where San Francisco excels. For their surf and yoga subcultures, Honolulu and Rishikesh score points for originality, but can’t keep up with the vibrancy of Las Vegas and other cities that never sleep.

The coolest cities, Amsterdam, Berlin, Copenhagen, New York and Tokyo, score high on multiple fronts. What doesn’t boost scores are attributes like glamour, exclusivity and newness, factors that amplify coolness for brands. In fact, places like St. Moritz and Dubai lose points for appearing too private or recent, respectively. But like a hot brand or shiny gadget, when a place seems cool, travellers are willing to pay more.

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However, in new research he’s conducting with more diverse participants, Kock has noticed culture can alter perceptions of coolness. “Rebelliousness is less of a coolness factor in Asia,” he says.

So, how much does coolness matter in the grand scheme? According to Kock, who plans to publish an index of the 100 coolest cities this month, nothing is cooler than being cool. “Coolness is the most powerful pull factor, more than price level, infrastructure, weather, safety, etc.,” he says. But, as all parents of teens must wonder, doesn’t what’s cool turn cringe faster than you can say “OK boomer”? “Coolness is dynamic,” says Kock, but he expects his urban parameters to stay stable. What’s more likely, he thinks, is that we will eventually call coolness by another name.

Whatever word Generation Alpha comes up with, keeping Portland weird or making an uncool area cool is complicated. “Coolness rarely comes from City Hall,” says Shawn Micallef, a University of Toronto lecturer and author regarded as an authority on Canadian urbanism. “There’s a risk of commodifying cool since it’s often rebellious and unofficial,” he says. Over–commodify, and you get kitsch. Over–sanction, you get cheugy. Get it right, and you might get over–tourism.

The more honestly a city comes by its coolness the better, and that comes down to the people, says Micallef. “A city’s cool when it’s lived in,” he says. Only then can it give way to the sidewalk ballet, the concrete cacophony, and the infinite jazz that invented coolness in the first place.

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