Side entrance to an old building in Hopkinsville, KY
This door, a side entrance to one of Hopkinsville's 1880s buildings, probably opens to a staircase. Perhaps the merchant's family once lived above the store, or perhaps the space was rented.
The window above the door enhanced the airflow to the second floor in hot weather. I believe a window above the door like this is called a "transom window."
The metal awning is too high and short to provide much shelter for a person opening the door in the rain. It probably did prevent rain from coming through the transom window, if the wind wasn't strong. The awning was surely added sometime after the building's construction. I doubt if it dates back to the 1880s.
This doorway is a side entrance to the Klein Building, on the corner of 6th and Main Streets. The front of the building, as seen from 6th Street, is pictured below. The Alhambra Theater on Main Street is visible in the background. The main entrance of the Klein Building sits diagonally at the corner, behind the black post that's supporting the second floor.