Detroit: Ambassador
Not for long!
If you're looking solely within the metropolitan area, I'd say the I-64 Hampton Roads Bridge Tunnel, but otherwise the US-13 Chesapeake Bay Bridge Tunnel connecting region to the Eastern Shore.
I would say that Norfolk/Hampton Roads are NOT the same metro area, as would
this Wikipedia article, who cites the census Bureau. Norfolk is number 37, and Richmond is number 49.
Anyway, I nominate Oklahoma City! And it would be the pedestrian bridge with that thing on top. Anyone who lives there knows about it, most don’t know what it is meant to be. At least from who I have talked to. It was supposed to be the state bird, but I can’t see it, lol.
And, for the Colorado Springs metro area, I would say the Royal Gorge Bridge. Although not technically in the metro area, it is not in its own metro area either, unlike the HRBT and CBBT example above.