The longest navigable underground river in the United States is home to countless blind and albino animals.

Nature and art meet in this curvy creation

This elaborate estate contains a stunning marble aviary, a sunken conservatory, and a magnificent music room with a two-story pipe organ.

A medical facility that has been kept frozen in time.

This former office building has been transformed into an immersive music venue and art space.

This mysterious hill seems to pull objects uphill.

At the turn of the century, a chair like rock sat at the top of the falls and hosted the winner of a local beauty contest.

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

If astronomy had a ghost, it would look like this observatory.