Once the mightiest machine on earth, this is about all that is left of Carnegie Steel’s Homestead Works. This mammoth steel making and processing plant covered hundreds of acres on both sides of the Monongahela River just upstream from Pittsburgh. All that remains now is a pair of blast furnaces and their supporting structures. This image does not show a blast furnace but does show some of the necessary support structures.
The following panorama from the Library of Congress taken in 1912 will give you some sense of the scope of the Homestead Works. The group of blast furnaces known as Carrie Furnace are just barely visible across the river on the far right in the gap in the smoke stacks.