 The Diamond Historic District encompasses 590 contributing resources.Although the Washington Square section of the Diamond Historic District--which is arrayed along Broad Street--was first settled by Europeans in the 1630s, the oldest surviving structure in the Diamond District is the c. 1825 Daniel Newhall House.Most of the District's earliest surviving houses are conservative, 2.5-story, center-chimney Federal buildings, but several Greek Revival structures also are extant.