The world's longest known cave system.

This national park on the shore of Lake Michigan features remarkable dunes that lie at the heart of a Chippewa legend.

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

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

A popular place to pick up prehistoric coral fossils from the time when Michigan was an ocean.

World's largest Christmas store.

This public baseball field is a beloved remainder from of one of the most historic stadiums in the country.

Lovingly nick-named the "Brick Dick" this municipal tower was winner of the World's Most Phallic Building Contest.

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

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.

Curious crustaceans support an obelisk from ancient Egypt that now stands in modern-day Central Park.

This whimsical group of statues is a favorite of children who love to climb all over Lewis Carroll's beloved characters.

12,000 sq. ft. museum tracing erotic art from antiquity to modern times.

This lush Florida island is home to the ruins of a crooked ship breaker's tiny empire.

A display of magnificent stained glass windows is the first exhibit of its kind.

Four glass boxes hover over 1,000 feet in the air to give visitors an unparalleled view of Chicago.

Hell on Earth is actually a small town in Michigan where anyone can be mayor for a day.

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

These enduring murals depicting a distinctly Marxist tribute to capitalism could not even be defeated by McCarthyism.

A Beaux-Arts triumph set to become Ford's innovation campus

The only surviving prototype for Buckminster Fuller's house of the future.

A sealed test tube said to hold Thomas Edison's dying breath was given to the inventor's friend and mentee, Henry Ford.

The 80-foot tire that looms over Michigan's I-94 was once a Ferris wheel in the New York World Fair.