At the top of the hour, this steam-powered clock's eight brass whistles play "Back Home Again in Indiana."

These pretty kitties killed and ate as many as 135 railway workers.

To find the "unicorns of the deep" you've got to go downstairs.

This building is a recreation of the gatehouse that separated Los Alamos from the outside world during the era of the Manhattan Project.

The world's largest set of the ten commandments lay nestled in the heart of the Great Smoky Mountains.

The largest puppetry museum in the United States houses the world's most complete collection of Jim Henson artifacts.

The remains of the iconic train crash from the movie 'The Fugitive' can still be found rusting along the Great Smoky Railroad.

Built by the patriotic residents of Boonsboro in a single day.

This striking Victorian Home with its 113-foot turret is best known as the site where abolitionist John Brown was executed in 1859.

This shale formation along the Appalachian Trail once inspired the third president of the United States.

Built in the 1850s, this church was of the first five churches constructed in Harper's Ferry.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

This advertisement for talcum powder was painted on the rock face and has since defied removal.

A local scoured more than 1,000 acres for stone to create his masterpiece.

One of the few surviving "Wigwam"-themed motels.

Amazing taxidermy dioramas from the 1960s in a cement building meant to look like an ice cave.

An abandoned theme park with a strange and tumultuous past.

Prehistoric animals decorate this popular outdoor park.

The world's longest known cave system.

This innocuous New Mexico storefront was once the secret jump-off spot for Manhattan Project scientists.

A monument dedicated to a local softball team full of clowns.

Once a dining hall for boarding school students, this lodge was a popular haunt for nuclear physicists working on the Manhattan Project.

This museum started as a collection of Manhattan Projects and continues to add exhibits as they are declassified.

A one-of-a-kind sundial at the Very Large Array honors a radio astronomy pioneer, incorporating the original piers from his breakthrough radio telescope.