Within a 3 km radius you can access 28 square kilometres. Central Paris, a classic walkable city, has a density of 6,500 residents/square kilometre. That's more

Within a 3 km radius you can access 28 square kilometres. Central Paris, a classic walkable city, has a density of 6,500 residents/square kilometre. That's more like a medium sized city you can have access to within 3km if you build for people instead of cars.