I've spent the last hour working through some of Katherine Marsh's The Twilight Prisoner:
In it Jack and his friend Cora travel to the New York City underworld and fly around the city as ghosts.
So far in the book they've visited the Campus of Columbia:
The American Natural History Museum:
And The New York Public Library:
Thus far, I am getting an excellent tour of a city that my one previous actual visit to involved a flight layover, during which I missed my connecting flight back to Pittsburgh. That did give me time to buy a "I *heart* New York" T-shirt though. Maybe I should find that shirt and wear it now....