When I showed up in Norman in 1972, Oklahoma Memorial Stadium was single-story and shaped like a block-U, with the north end closed. The School of Architecture had classrooms inside the north-end structure. The south end had moveable bleachers that partially covered (IIRC) a baseball practice field and were moved out of the way when needed. There was gameday parking on that field. There was a dirt track--used for the indoor track season--underneath the seating areas. Capacity was 62,000. I can't find a picture of it online.
Now it's this.

The bleachers that were south end-zone seating in 1972 have been replaced by the bowled-in complex at the left end. Upper decks have been added on both sides. Capacity is 80,000+. I imagine that the next major renovation will be to remake the west deck to match the double-layered-with-luxury-suites east deck. And then probably to wrap the deck around the north end.
As CD said about the UNC campus, it seems like there are more trees now than there were 49 years ago. When David Boren was University President, his wife spearheaded many campus-beautification efforts, and the campus is much more attractive now than it was then.
I sat in the Zone at Kyle Field at the 2006 OU-A&M game. When I watched the Bama at A&M game this year on TV, I hardly recognized the stadium as being the same structure I saw 15 years ago.
I saw the Army-UNC "game" (62-8 Tarheel win) in 1982. I was impressed with the UNC campus. I had spent Sep 1980-May 1982 at Fort Bragg, so I was reasonably familiar with the familiar with the scenic beauty of parts of North Carolina.