New York is a state in The Northeastern region of the United States of America. It was one of the original thirteen colonies.
New York, mainly the New York City Metropolitan area, have appeared in all the books to some extent.
The main locations of the state seen are Camp Half-Blood on Long Island and Manhattan as seen in visions from the dagger of Piper McLean. Keeseville in upstate New York is the prime location of the short story Son of Magic in The Demigod Diaries.
Manhattan and Camp Half-Blood are the sole locations for The Hidden Oracle.