In addition to the visual aesthetic that obviously attracts me to abandonements, one of the things I enjoy about this hobby is having the opportunity to learn a little bit of history about the places I visit and be able to see visual evidence of a site's previous use.
This particular complex was built in the 1800s as a fort, it was then used as a barracks, prison, and even a military hospital. While exploring here, if you're observant, you'll definitely see traces of each of these uses.