Funny you mention I-75.
My brother and I grew up in Lincoln Park, MI just south of Detroit. We were reminiscing just last night about when that freeway went in, sometime around 1968, a couple of blocks from our house.
We'd spend hours riding our bikes on it before it was opened. It was great, like a private freeway just for us kids.
Unfortunately, that damn freeway cut Lincoln Park in half, and it never was quite the same after it opened. I just checked Zilla last night and the house we grew up in sold for $12,000 last year.