Collapsing castle on the Hudson river was once the storage site of military surplus business.

A 16th-century horror show built in a lovely Italian garden.

A recreation of the doomed ocean liner in the middle of the Smoky Mountains.

The massive, original Colgate Clock is mounted on a defunct factory building that was once a prison.

Indiana's shrine to the sport that has become a hallmark of their culture.

The site of a 19th century "dream city" that almost rivaled Chicago before being swallowed by the Indiana sand dunes.

The chiseled jaw of this forgotten American hero still stands tall in a small Indiana town.

Covered in tens of thousands of coats of paint, this Indiana attraction holds a world record all its own.

The first artificial white water river course in North America cuts right through an Indiana city.

The world's largest anatomically accurate brain sculpture.

The only freestanding table rock formation east of the Mississippi.

One-layer pyramid in Indiana.

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

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

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

A giant concrete egg marks this Indiana town as the "Egg Basket of the Midwest."