> When I started primary school at the age of 7 I walked to school, it was like a mile away.
The US is about thirty times larger than Poland and much of it was developed after the wide adoption of automobiles. Few children live within a mile of their school here, and of the ones that do, there are often not walkable routes to get there. Many roads in the US have no sidewalk and are intended only for vehicle traffic.
In the 60s - 80s, most kids walked to school unassisted. This was the norm. I used to walk 1.5kms when I was 5 and today, my kids walk less than 500m. Still, helicopter parenting and Political Correctness has (as another poster stated) almost made this a crime.
I am one of the few parents that trusts their own kids to walk a short distance to school by themselves. I have received a few comments from other parents implying negligence for trusting my kids.
I have doubts that it's busy roads that changed this behaviour.
The metro areas include a great deal of sprawl where the schools (and even the drugstores) are separated from residential subdivisions by several miles of fast roads with no sidewalks or bike lanes.
Look for the percentage who actually live in the cities, vs. the metro areas.
I live in the District of Columbia, call it three miles from downtown. The high school students in the neighborhood who are in public schools attend Wilson High School or one of the district's magnets, namely School Without Walls and Banneker. Banneker might be a mile and a half away, Wilson and Walls are more like four miles. I will say that it appears to me that most of them take public transportation to and from school.
And when I lived in the Denver suburbs, my brother attended a couple of county schools. The junior high was at least a couple of miles away, the high school more like five. Do not underestimate American sprawl.
The US is about thirty times larger than Poland and much of it was developed after the wide adoption of automobiles. Few children live within a mile of their school here, and of the ones that do, there are often not walkable routes to get there. Many roads in the US have no sidewalk and are intended only for vehicle traffic.