Pennhurst Asylum ranked #1 by Hauntworld.com, occupies the very real structure that once housed the Pennhurst State School, an institution for mentally and physically disabled patients that was opened in 1908. After 60 years, the school was shut down by reports of unorthodox behavior among the staff, leaving the enormous structure abandoned and rotting. Enter Pennhurst Asylum, which has transformed the administrative building into an award-winning haunted house. The real-life history of terror is the foundation for an elaborately designed production that uses animatronics, digital technology, and costumed actors to recreate the building's past.

CGI effects and costumed actors re-create the medical experiments and the creatures they've yielded. A visit features encounters with old in-patient cells, a 900-foot-long tunnel outfitted with catacombs, and a ghost hunt in the Mayflower building, which is believed to be the most haunted of the State School's original structures. During this part of the visit, guests are given a flashlight and allowed to wander the original dorms in search of sights, sounds, and echoes of the original inhabitants.