When I grew up, in the late 80s/early 90s, we'd be outside like 90% of the time. This was in rural northern Europe, and from my memories, parents there just used to send their kids out. The few times we were allowed to be inside, we really had to ask nice.
Outside activities included playing soccer, biking around, exploring places, building stuff.
It is such a huge contrast to my peers / people my age are raising their kids now. Some of the parents are basically hovering over their kids from 7 in the morning to 9 in the evening. It's non-stop.