New York, USA
Home of Camp Half-Blood
Long Island is located in the southeastern part of New York, Percy Jackson's home state, aside the Atlantic Ocean. To the north is Long Island Sound. Camp Half-Blood is said to be located here, at 3.141 Farm Road, Montauk. Sally Jackson also rents a small beach house on the shoreline where she sometimes takes Percy during the summer. Long Island is also where Sally met Poseidon. It is also breifly mentioned in the Kane Chronicles, where a strange magical frequency was emitting from.
Long Island is home to Camp Half-Blood and is a location in every single book.