We bought our first house in Pittsburgh in 2010. In an experience that I now know is very familiar to homeowners in my neighborhood, we knocked out some low ceilings to reveal Victorian-era wallpaper, and remnants of a window that was bricked in and turned into block glass. There used to be a second staircase here, and the aging former owner, living only on the first floor, turned it into a full bath. It's since been opened up (we didn't replace the stairs), and the window is back to its old size. It's hard, dirty work, but all around us, people are doing the same thing, and it's exciting to see the archaeological nature of the things people discover, literally right above their heads.