The Trans-Allegheny Lunatic Asylum is Weston's unavoidable sight: a huge, pale sandstone hospital stretching across the edge of town like a misplaced Gothic university. It was built in the 19th century as the Weston State Hospital and remained in use for more than a century before closing in 1994. Today it is a museum and tour site, with the building's architecture, medical history, patient stories, and paranormal reputation all folded into the visit.
Take a daytime history tour if you want the strongest version of the place. The guides explain the Kirkbride layout, the Civil War-era construction, and the later overcrowding that changed the hospital's story from idealistic reform to institutional failure. Ghost tours and seasonal events are popular, but the building is interesting enough without leaning on scares.