The world's longest known cave system.

A bizarre roadside attraction and the first instance of miniature golf in the world.

At 207 feet, one of the world's longest continuous escalators.

A monument celebrating the idea of reaching inaccessible places.

"We Seceded Where Others Failed."

Arrr! The most authentic collection of pirate artifacts in the world... matey.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

Former self-sufficient mental institution now a planned community.

The largest earthwork effigy in the world.

A castle built by an eccentric medieval enthusiast in rural Ohio.

Ancient petroglyphs discovered only after a massive fire swept across Michigan in the 1880s.

Deep scars on the earth left by the Ice Age.

Take a drunken tour inside the world's largest known geode.

Largest magic museum in the United States with more than half a million pieces of memorabilia.

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

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

The city is full of whimsical portals to another world.

Center filled with hands-on displays served as a tribute to several astronauts with connections to the state.