I've hearnd rumors of this idea, but I actually didn't think too much of it at first. I wasn't sure that it would really make that much difference to have a National Park in Delaware. I understand that Delaware is the only state without one, but does the distinction of being called a "national park" really make much difference? Maybe it does. I say that after reading Will Delaware Get a National Park?
While my first choice would probably be Fort Delaware, an underwater marine park off Cape Henlopen would also be great.
