A big, square, wooden barn
They came to America with German settlers (See the Pennsylvania Dutch), and were a common sight in the 1700s and 1800s.
The "new world dutch barns"* tend to be large square buildings made from wood planks (both walls and roof). They have large double doors at both ends for wagons, and smaller doors at the corners for people and livestock. They're built on a H-frame (sets of two upright support beams with a connecting cross beam), which may be used to divide the barn into bays. Other times, the barn may be left as one big open room, perhaps with a small loft.
The barns are probably most famous for the bright hex signs that were often painted on their sides, to ward off evil spirits.
*I don't have any information on old world dutch barns
. Nor does Google.