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

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

Equal parts record-breaking temple to consumerism and bizarre fun park, it's more than you think it is...

Island where motor vehicles are banned -- home to the only carless highway in the United States.

This shallow cave got its name from copious amount of human bones found inside.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

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

Controversial tribute to the heavyweight champion boxer who grew up in Detroit.

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

The twin towers in this Chicago fountain use 50 foot tall video screens to spit on people.

The unluckiest U-boat in the entire German fleet is now on display in a Chicago museum.

This historic Illinois "Muffler Man" has been converted from axe-touting lumberjack to rocket-wielding space ace.

A tribute to one granddaughter's old apartment which now represents the whims of each visitor.

The world's longest known cave system.

Prehistoric animals decorate this popular outdoor park.

The remnants of two World's Fairs are here, complete with a 12-story globe, a mini-Manhattan, and a UFO-shaped pavilion.

Experience a charming 1930's version of "infotainment."

Lucha Libre (Mexican Wrestling) themed taco shop.

A building so large that it has its own weather.

One of the only Florida forts to remain in the hands of the Union all through the Civil War still stands as a historic stronghold.

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

This prehistoric sinkhole lured exclusively male mammoths to their death, much to the delight of science.

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

The highest point in South Dakota contains the ashes of Valentine McGillycuudy, the "Holy White Man."