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

This freshwater spring fills with 10,000 gallons of water per minute.

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

The largest hot spring in the United States is, as the name suggests, a stunning show of natural color.

A museum dedicated to the history and exploration of both popular music and science fiction.

A beautiful geyser under environmental threat.

Home to items never before seen by the public.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

The first declared National Monument in the United States.

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

A roaring, awe-inspiring double cascade of icy water flows through woodland Oregon like something out of a Tolkien novel.

Canada's oldest sugar maple has been growing since around 1500.

305 homemade stone stairs wind their way up the Hamilton escarpment.

To truly appreciate Detroit's landmark skyscraper, you have to step inside.

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

The world’s largest Masonic temple was saved by the White Stripes.

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

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.

The Incredible Hulk, Yoda, Mulder and Scully, and many many others watch over the mean streets of Toronto.

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

The Victorian-era greenhouse is stuffed with tropical plants, and open 365 days a year.

A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

A book collector's dream, this Toronto bookstore has the world's first "Biblio-Mat," a random book vending machine.

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