There is the Antioch Bridge and the Golden Gate Bridge and the Bay Bridge. Also quite a few bridges within the delta where I grew up. But for the most part, I personally only crossed these bridges for vacations, for fun. I drove over and under A LOT of overpasses though. If you've seen the movies with shots of LA traffic and all the freeways, I've lived there. And the Bay Area, CA, has it's fair share of interchanges.
Here near McComb, I go over a lot of bridges, too. Most of them are over water. Little creeks, rivers, low spots where water collects after the rain.
It just hit me the other day that I don't have a lot of freeways to go over or under, but I still see a lot of bridges. Not to forget one of the longest bridges in the United States that stretches over the Louisiana bayou.