If we can throw in provinces, Ontario is probably Niagara Falls. I guess the CN Tower would be second.
I’m originally from Louisiana, and my first thought was a cypress bayou. But that’s probably a bit nebulous. Perhaps the Lake Pontchartrain Causeway (the longest bridge over continuous water in the world)? Or the Superdome?
The weird thing with New Jersey is that our most Iconic sight is the NYC Skyline. Things we do have is the Shore and the Battleship New Jersey. In my area it is probably the Twin Lights sitting up in the Highlandslooking out to sea.
Lake Superior
I live on the WA/ID border. For WA, I’d say Mt. Rainier. Space Needle is fairly good, but too Seattle specific for me.
For ID, I’m not sure what is our most iconic sight. Craters of the Moon? Hell’s Canyon? Wait, it just came to me! The big ID potato! It’s going to be touring the US so it could be coming to you next! I bet you all are excited 
Hey, you can’t have that one, it’s mine!
A “This Car Climbed Mt Washington” bumper sticker.
No that I’m aware of. Perhaps you’re thinking of the Great Gulf?
My dad was a friend of Mario’s. What an interesting guy he was.
Maryland: Fort McHenry or the Chesapeake Bay Bridge
At least in my experience the Bell is more a national symbol than a PA symbol. Lots may have started here from its sound but the image doesn’t seem as connected to the state and the Revolution and Congress.
And although I realize it was partly in jest – as the film has aged I find a lot of people in their 20s and younger have no idea who or what that statue is unless they are from Philly. And move further out to other states and most people think of it as “that ugly potato statue”. (Always hated the thing myself)
We actually have a lot of those in Pittsburgh having our own (almost) famous Mt Washington.
There were just two new Creed (Rocky) movies. Every time I drive past it there’s a big crowd around the statue waiting for pictures. Although for iconic I would pick the museum steps and not the statue.
I would have gone with Independence Hall & the Art Museum steps (which Rocky ran up). There are still busloads of tourists who get off & run up the steps & raise their arms at the top.
12 Apostles?
Dunno for round here- the arse end of a tractor going at 5mph in front of you on a road not quite wide enough to overtake is certainly one of the commonest sights…
Never heard of it.
Perry’s Memorial is famous and iconic. It’s anything but “piffle.” If anything, your roadside freak show is the piffle.
My immediate thought was Bourbon Street.
I’ve lived in DC, and I say the Capitol dome. Either by itself or paired with the obelisk.
I think you could reasonably say “the National Mall”. That gets you the iconic “Lincoln Memorial, Washington Monument, and U.S. Capitol all lined up in a row” shot. (The White House, especially that view from the South Lawn, would be a strong runner-up. Some states and state-level entities got nothing, while others have, like, all the iconic spots.)
The Washington Monument can be seen for quite a ways all around the DC area, so that’s the one seen live the most. For most people though, they’ve seen the Capitol building and the White house in pictures, movies, and television far more often.
Here in RI the US Capitol isn’t all that interesting. Here’s our State House.
Since my current state has an obvious iconic sight, I’ll go over all the states I’ve lived in:
Pennsylvania: Independence National historic Park - this gives you both the Liberty Bell and Independence Hall. If I had to pick one I would go with Independence Hall.
Massachusetts: Old North Church, with one light in the belfry.
New York: Any view of the Manhattan skyline that includes the Empire State and Chrysler buildings.
North Carolina: The Old Well at UNC.
Wisconsin: I got nothing. A frozen custard stand? A landfill converted to a ski area?
Arizona: As I said, obvious. The big hole in the ground.
Strong disagree. It’s Arlington Cemetery by a mile.