The Winthrop Center/Metcalf Square Historic District encompasses the historic center of the city of Winthrop, Massachusetts. Although the area was settled early in Massachusetts history (c. 1637), the Winthrop peninsula remained sparsely populated until the 19th century. Its central area did not begin significant development until there was some industrial development in the first half of the 19th century, and accelerated with the arrival of the railroad later in the 19th century. It is centered on Metcalf Square, at the junction of Pauline, Hermon, and Winthrop Streets; the district extends northward along Hermon and Winthrop, and also includes properties as far east as Cross Street.