The Newburyport Historic District encompasses most of the historic downtown area of Newburyport, Massachusetts. It is roughly bounded by the Merrimack River, Marlboro Street, Ashland Street and High Streets. Covering some 750 acres (300 ha) of land and more than 2,500 contributing buildings, it includes the most populous part of the city, and a panoply of architectural styles, dating from the 17th century to the early 20th century. The district was added to the National Register of Historic Places in 1984.