Well if you had to pick a state, I would say Either New York or California. If we didn't feel like using either of them, it would simply be a Northeastern State next to the sea.
I'd wager Maine, most likely. Due to the high cliff sides on the edges of the beach, plus "Cape Doom" (I think it's called that...) with a lighthouse. There a lot of lighthouses in Maine, I mean their known for that I think.
But then again, that's just the cartographer's opinion.