What I did
First, I created a list and google maps-scraped "essential" amenity
locations – grocery markets, pharmacies, parks, schools, and so on. Next, I cleaned the
scrape data, and mapped these locations' 15-minute walk zones using QGIS, and their
overlap. These overlapping amenity-access zones would be 15: neighbourhoods.
To understand just how many people can live in and enjoy a 15: city, I overlaid my 15:
zones on a population density map. And to get a rough idea of who can afford to live in
these 15: zones, I superimposed my 15: maps on a median household income map.