An enchanting natural wonder in Puerto Rico's Camuy River Park.

A mine fire has been burning under the deserted town since 1962, but this church is still going strong.

Step back in time on this preserved 1800s farm.

Some North Carolina Cherokee have been keeping their history alive for decades with a single play.

The secret city built by the Manhattan Project.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

More than five miles of underground passageways.

One of the last active volcanoes on the Eastern seaboard.

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

Mile-long cave system near Great Smoky Mountains.

Paranormal investigators claim this abandoned asylum is the most haunted spot in the eastern U.S.

This disastrous New Jersey safari park saw animal attacks, escapes, and disease before being abandoned.

These mysterious petroglyphs in Vermont reflect a troubled history in the treatment of Native American culture.

These rows of World War II-era bunkers were the scene of some of the infamous Mothman sightings.

This ghost town was once a cult-like religious utopian settlement.

Garden dedicated to native carnivorous plants and site of huge flytrap heist.

The skeletal white beams stand as a monument to religious dissent.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

Bigfoot prints, Feejee mermaids, and haunted dolls on display in a tiny North Carolina town.

An abandoned 1920s school with a mysterious history.

An abandoned village that doubled as "The Hunger Games"' post-apocalyptic wasteland is up for grabs.