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

A six-story-tall golden pyramid, surrounded by a moat.

Taxidermy, Cigar Store Indians, A Model of a New York Tenement and Delicious Draft Root Beer.

This modest post office sits on the site of H.H. Holmes' famous murder castle.

A replica viking ship from the Chicago World's Fair is still in dry dock in an Illinois park.

When you visit his grave, be sure to rub the Great Emancipator's nose for good luck.

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

In one Chicago park, a trio of werewolves are waiting to devour their fallen brethren.

Once one of the world's great cities, Cahokia was a place of religious worship, trade and mass human sacrifice before being mysteriously abandoned.

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

A little-known subterranean street runs under some of the best-known buildings in Chicago's River North.

What may be America's largest classic video game arcade lurks inconspicuously in a Chicago suburb.

This elaborate Hindu temple is located in a Chicago suburb, but looks like it was transported directly from India.

Chicago's North Park Village was once the largest municipal sanatorium in the country.

River pirates, murderous bandits, and serial killers used this Illinois cave as their debauched hideout.

At Chicago's revered Field Museum, visitors are invited to learn about and literally explore DNA.

This $3 million model train takes you through Chicago, Seattle, and the thousands of miles in between.

Cemetery featuring rare glass-fronted columbarium.

Each of these gorgeous, intricately decorated rooms is painstakingly crafted to the scale of 1 inch: 1 foot.

Years of archaeology, just chillin' by the water cooler.

All of Chicago's wood-paved streets are long gone but two alleys remain.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

What was once one of the country's largest confectionary plants is now an abandoned ruin, but is still pretty sweet.

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