The 13th Gate
Cinematic sets, underground caves and a genuine swamp crossing.
The 13th Gate is regularly called the most detailed haunted house in America, and the detail is the point: underground caves, a full swamp sequence, a crematorium and a cemetery, built to a standard that reads as film production rather than seasonal attraction.
If you only visit one American haunt that is not attached to a theme park, most people in the industry would tell you to make it this one.