Ghosts of a bizarre plane crash and a mysterious underground city point to powerful forces at work inside Grand Canyon National Park.
A tragic plane crash, shocking murders and a mysterious python infestation suggest a dark, evil power deep in the heart of Florida's Everglades National Park.
Believed to be the work of Pele, the fire goddess, black magic, mysterious deaths and violent fireballs haunt Hawaii Volcanoes National Park.
A Bigfoot-like creature and UFO sightings suggest that California's Joshua Tree National Park may be ground zero for alien genetic experiments.
While some believe the random flashes of light at Glacier National Park in Montana are evidence of extraterrestrials, a trail of clues leads to an even more shocking theory: that the technology causing them may be Nazi in origin.
Unexplained disappearances, a mysterious death and a Karuk Indian legend are linked to a race of superhumans in California's Shasta National Forest.
The fabled chupacabra, which many believe lives in Puerto Rico's El Yunque National Forest, is linked to various UFO sightings and a secret US government research facility in the area.
Ghost sightings, a secret government time-travel experiment, and Native American battles suggest that Pennsylvania's Gettysburg National Military Park is a place of unusual and mysterious power.