The Sandy Hook Lighthouse, located about one and a half statute miles (2.4 km) inland from the tip of Sandy Hook, New Jersey, is the oldest working lighthouse in the United States. It was designed and built on June 11, 1764 by Isaac Conro. At that time, it stood only 500 feet from the tip of Sandy Hook; however, today, due to growth caused by littoral drift, it is almost one and a half miles (2.4 km) inland from the tip. It was listed as a National Historic Landmark in 1964 and added to the National Register of Historic Places on October 15, 1966, for its significance in commerce and transportation.