Bad farming practices caused this unnatural natural wonder.

They call this long foot bridge a swinging bridge, but really it's the bouncing you have to watch out for.

This angular brutalist playground turns playtime into modern art time.

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

Though its branches are painted bright colors by generations of locals, the tree is said to be a haunted portal to hell.

The remains of one of America's first radiation testing grounds still rest ominously in a Georgia forest.

The ruins of a cotton mill that was burned in the Civil War are still hidden in a Georgia forest.

An underground magnet for ever-changing street art.

One of the largest-ever mental hospitals now sits abandoned, surrounded by 25,000 unmarked graves.

A theme park that suffered massive flooding during Katrina was abandoned, and now proves irresistible to trespassing explorers.

This Florida arena, once host to "the fastest game in the world," has sat empty for 25 years.

This abandoned bridge is now a favorite haunt for graffiti artists.

An FDR-era tuberculosis sanatorium has stood abandoned in the suburbs of the U.S. capital for over 30 years.

An eerie, decaying ghost town destined to fade into the forest.

This abandoned asylum was once a state of the art facility before devolving into one of the most deadly mental institutions in American history.

These beautiful ruins deep in the Pennsylvania woods are thought to have been a ski lodge or a speakeasy, but no one really knows.