NEW YORK (AFP) - A shy New York woman, whom no one took to be wealthy, left a shockingly happy surprise when she died: US$20 million (S$24 million) in donations to the city's libraries and main park.

Ms Mary McConnell Bailey lived modestly and volunteered at a hospital and schools, before dying at 88 last year, the New York Post newspaper reported on Tuesday.

Now, the Post says, it emerges that the New York Public Library and Central Park Conservancy recently received cheques from her estate worth US$10 million a piece.

"You would have never known" she was rich, the Post quoted her former best friend and neighbour, Ms Lizanne Stoll, as saying. "When we went to lunch, it was usually Dutch," she said, meaning everyone paid for themselves.

The library's top donations official told the newspaper he'd met the unassuming Ms Bailey often, but couldn't remember her voice. "That's how soft-spoken she was."

According to the Post, Ms Bailey came from a wealthy family and moved to New York in the 1940s, then inherited a fortune. However, she spent little and lived in a basic Manhattan apartment.