data.newsday.com — The National Register of Historic Places lists nearly 400 sites across Long Island as special places worthy of preservation. From Sagamore Hill, the 23-room Victorian home of Theodore Roosevelt, to the estate of William Floyd, a signer of the Declaration of Independence, to the lighthouses that dot the shores and the many community treasures that often go unnoticed, the sites listed on the National Register are representative of Long Island's deep, rich history.