This barn was built in 1920. It is in five distinct sections. The far end (the small door) has a concrete floor, and I suspect it was designed for pigs. The next section (bigger door) has got a raised floor, just like the milking section of the barn where I grew up.
The next section (big open door), we call the breeze way, and it appears to have been used to store farm vehicles, Probably wagons originally, and then later tractors and trucks. At some point a “nose” was added to the north side, which looks designed to accommodate the front end of a grain truck.
The west section (big closed doors) was probably for horses. The walls seem designed to provide a certain amount of ventilation, just like a corral.
Finally, above the east two sections, is a hayloft. Note the cupola on the roof for venting the cattle and pig sections.
(First Posted on Facebook in 2016)