This large midwestern cavern features impressive rock formations and an underground waterfall.

Giant pinnacles in the sun-scorched lands of Southern Utah have been nicknamed "white ghosts."

These Great Lakes sea caves accessible by boat in the summer turn into temples of ice reachable by foot in the winter.

Once connected to the outside world by a single train track, this ghost town is looked after by the National Park Service.

Japanese gardens dedicated to the Japanese farmer that refused to throw in the trowel.

A historic covered bridge, only one of two remaining in North Carolina.

Rare recess caves fill this unbelievably beautiful Ohio park.

This narrow canyon has been carved by the river over thousands of years into spectacular and curious forms.

Bad farming practices caused this unnatural natural wonder.

The only remnant of a small mining town is an abandoned railroad tunnel that is steeped in ghostly lore.

This concert pavilion on the shore of the Great Salt Lake has been destroyed by fire, water, and disinterest but keeps coming back.

Despite being one of the most photographed vistas in the Rockies these twin peaks are rightfully known as the "Deadly Bells."

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

A stunning, abandoned limestone quarry in southern Indiana provided the stone to erect the Empire State Building.

One of the most scenic falls in Massachusetts has a history of death and grim legend.

Once an ambitious nature spa, these forest ruins now provide a serene monument to failure.

Shop of curiosities with a dinosaur museum tucked in its basement.

Half of a waterfall goes into the river while the other half seems to disappear.

A secretive collection featuring objects that were designed specifically for U.S. intelligence operations.

Who needs fancy modern water slides when this giant North Carolina rock works just as well?

One of the oldest living oak trees in the Southeast.

An inconspicuous footbridge beloved by San Diego locals.

Dig for your own trilobites in this goldmine of invertebrates.

A half-mile long and three stories high, this bridge over the Des Moines River Valley mimics a descent into a mine shaft.