Definition of 15-min city: https://www.cnu.org/publicsquare/2021/02/08/defining-15-minu... & https://hub.beesmart.city/en/strategy/the-15-minute-city-nur...
This may come to fruition in private charter cities like Telosa, https://www.cnn.com/style/article/telosa-marc-lore-blake-ing... & https://cityoftelosa.com/
> A so-called "15-minute city design" will allow residents to access their workplaces, schools and amenities within a quarter-hour commute of their homes. Although planners are still scouting for locations, possible targets include Nevada, Utah, Idaho, Arizona, Texas and the Appalachian region.
Neighborhoods of existing US cities may also be candidates, https://www.movebuddha.com/blog/15-minute-cities/
> One popular concept hailing from Paris is the 15-minute city. It’s a city in which, wherever you live, everything you need is located within a 15-minute walk or bike ride away ... which of America’s largest cities have the greatest potential for transitioning into a 15-minute city?