An underground wonderland in Iowa.

A remote hill on a stretch of country road where the laws of physics are defied... or so it seems.

This lush 12-acre site was once named the finest Japanese garden in North America.

Walk along the intricate path of this stone labyrinth and gardens.

Former hotel turned into haunted playground.

This monolithic statue was erected in honor of Chief Black Hawk (even if it wasn't made to look like him).

A museum showcasing the life of "Buffalo Bill"

You were once able to challenge a chicken to tic-tac-toe at this park, which is now converted into the Aikman Wildlife Adventure.

A preserved factory in the "Home of the Carrousel" is now a museum dedicated to the classic wooden ride.

This museum devoted to the gothic author holds such interesting ephemera as his socks and walking stick.

A once-booming Mississippi River town with a history of racial violence is now eerie and mostly abandoned.

A century-old hotspot for jazz, frequented by everyone from Charlie Chaplin to Al Capone.

This whimsical Oz-themed park had a wonderful impact on the surrounding neighborhood.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

This historic house museum that celebrates one of the world's most influential social reformers is also one of the most haunted locations in Chicago.

What's left of the ruins of the 1893 Columbian Exhibition, or World's Fair, also known as the White City.

This simple home was the beginning of a long journey for the iconic Western film star.

What was once a presidential estate is now an exotic menagerie and home to the Budweiser Clydesdales.

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

Megachurch turned Catholic church comprised of 10,000 glass panes.

An 18th-century viewpoint across the surrounding highlands.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.