The ’15-minute city’ might not be realistic for North America, researchers findMcGill study suggests a '30-minute city' is more attainable, though would still require urban design changes In the "15-minute city," a concept popularized in Europe, everything a resident might need on a daily basis is a short walk or bicycle ride away. A study by Transportation Research at McGill University (TRAM) suggests, however, that this model may not be easily achieved in large North American cities such as Montreal.