Built in 1869, this now-retired structure looks more like a medieval fortress than a county lock-up.

A river with some unusual, and occasionally dangerous, habits.

This softly rounded mansion was built without corners not to avoid evil spirits, but to make them more comfortable.

This national park dedicated to the tallgrass prairie ecosystem still displays its military past.

This tiny historic jail along Route 66 is the perfect fit for exactly one criminal and their partner-in-crime.

Meant for a railway that was never built because of the Great Chicago Fire, these piers still stand nearly 150 years after they were installed.

The face of a woman pushes its way through the earth.

What was once the second largest steel mill in the US is now a sprawling complex of modern ruins.

A small abandoned and abused cemetery that has become a magnet for ghost hunters.

The final resting place of two unknown soldiers.

A hidden grotto on the grounds of the Kane County Government Center.

This cemetery is all that remains of a school for "wayward" girls.

Arguably the best example of an authentic Dutch windmill in the United States, rivaling its counterparts in the Netherlands.

Museum dedicated to the art of cutting and polishing stones.

This overgrown Illinois water park offers a whole new type of adventure.

Cold War missile launch site which has been converted to a public park.

An exhibit of items from the mental institution where Mary Todd Lincoln lived after her son conspired to have her committed.

Burial mounds of prehistoric Native Americans who lived along the DuPage River.

Tucked away amongst townhomes lies a restored, early 20th-century tea house and garden, the only remains of a historic estate.

The final resting place of the world's first nuclear reactor.