 In the Nazareth area, this was caused by the completion of the nearby Pennsylvania Route 33, which ran north and south, thereby connecting Interstate 78, U.S Route 22, and Interstate 80 (all of which ran east–west), and the completion of the Interstate 78 southern Lehigh Valley corridor high speed interstate, which connected the Lehigh Valley to New Jersey and New York to the east, and Harrisburg and Pittsburgh to the west.The Nazareth Historic District was added to the National Register of Historic Places in 1988.As of the census of 2000, there were 6,023 people, 2,560 households, and 1,515 families residing in the borough.