Thornburg Historic District is a historic district in Thornburg, Pennsylvania. It was planned as a suburban development in the early 20th century and has 75 contributing buildings, all but one residential. Though only 4 miles from downtown Pittsburgh, the district remains intact as an example of early suburban development. The majority of houses were built in the Bungalow or Shingle styles, with others in the Queen Anne, Craftsman, Colonial, Mission or Tudor styles.