I've been to the following in my life time so far:

MLB
Oriole Park at Camden Yards (Orioles, of course)
Citizens Bank Park (Phillies)
Nationals Park (Nationals, of course)
PNC Park (Pirates)

Minor League Baseball
Ripken Stadium (Ironbirds)

NFL
M&T Bank Stadium (Ravens)
Lincoln Financial Field (Eagles)
Memorial Stadium (Ravens first ever home game)

NCAA Football
SECU Stadium (Maryland)
Navy–Marine Corps Memorial Stadium (Navy)

I wished I didn't go so late into the seeing other Stadiums thing.

Dodger Stadium
Oakland Coliseum
Wrigley Field

1 or 2,not many.......

Busch Stadium
Kiel Center/Savvis Center/Enterprise Center

Busch Stadium in St Louis when I was in the 6th grade. The only time I have ever been to a major professional sports game.

Liberty Bowl in Memphis (from Memphis).

Vaught Hemingway Stadium, University Mississippi.

The University of Tennessee stadium, whatever it’s called….