The Little Red Lighthouse..
..and the Great Gray Bridge. I never thought an 18mm lens could be so tight.
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Check out the September contest: LINE!
All of them.
My favorites are the first and last. The first for the angle and the last for the juxtaposition of the lighthouse and the bridge. 
Yes, do check out our monthly contest. The theme is Lines, and you have some superb examples here.
Though if I have a submission I'm always in. I'll have to check now 
Edit, I did know lines were the theme (I thought that was last month, though) - and the first thing I thought was "I have footing access to the GWB, piece of cake!" Time to submit, though I have even better in the archives..
Do I use #2 here, with the lines gracefully arching away? The unpublished one of the abutment, with two perpendicular yet canted lines slashing the sky from sight? #3 here, with the straight, towering column overwhelming the little curved house? The shot directly under one tower, with the deck evenly splitting the frame?
Decisions, decisions...it would help if I didn't suffer from the Dunning-Kruger effect in my photography 
One of the reasons that I like #2 best in the set you posted was because #1 and #3 aren't "pretty" with all the rust on the girders. But that is just me---I was bothered by that, but I am obsessive about some things, like "perfection" without flaws---and that isn't real. I also felt that 1 and 3 were "too busy"....just too much chaos for me. But I know that some people prefer them for the interest that all the lines creates.
Don't listen to my ranting. We all have an eye for different things. Good luck finding just the right one. Mine will probably be boring. 
The bridge from the center of the park underneath: I was surrounded by families grilling burgers and dogs, on the breezy salty riverfrint, the perfect American scene; then you turn around and the sky itself is cut apart by the towering, well, tower, and the deck slashing across the blue to the unnatural, angular, grey concrete abutment standing out from the organic forest:
