Waverly Hills Sanatorium was an abandoned sanatorium Sam and Dean visited in order to collect the many ghosts haunting there.
In their bid to defeat the Darkness once and for all, Sam Winchester formulated a plan to use souls to build a destructive bomb. Unsure of where to gather enough souls, Dean suggested this sanatorium.
The boys entered the place and began hunting the souls down. Once they had collected everyone, Billie the Reaper came and took notice of their actions. She decided to help them create their bomb.
Since the bomb was ultimately deactivated, it is unclear what happened to the souls who once haunted this place.
- Waverly Hills Sanatorium is a hospital in Kentucky, used in the 20th century for people with tuberculosis. It is reputed to be one of the most haunted places in the US.
- According to Jared Padalecki, he suffered a bad allergy attack while shooting the scenes at this location.