Why do they call New York the big apple

Question

Why do they call New York the big apple

Answer 1

The last I heard, no one knows why it's called the Big Apple.  Back in the 70's the mayor Abe Beam was asked, because he'd lived in the city for his whole life, and he said he didn't know, either.  The term Big Apple was used in the early 20th century, but where it came from nobody knows.