The fairy tale castle of the "fairy-tale king."

Most-visited and most-photographed slot canyon in the American Southwest.

An artsy hidden staircase leads to breathtaking views of San Francisco.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

One part local history, 99 parts gruesome haunted house.

Largest lake in Great Britain measured by surface area.

Old-fashioned knowledge and modern engineering create the world's only rotating boatlift.

360° views of the city plus five floors of optical illusions and hands-on science.

This Scottish manor house is a lush relic from the life of a literary great.

Northern Ireland's Brobdingnagian stepping stones.

What happens here stays here – unless it affects the whole world.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Built as a gift to the hottest tastemaker of the time, these hidden quarters remain an Art Deco showpiece.

The large fjord lake is thought to be the home of "Ogopogo," a giant sea serpent.

This massive mall has hundreds of shops, an amusement park, and a history of deadly amusement attractions.

The only road through the heart of Glacier National Park.

Nestled near the mountains of western Canada resides this behemoth earth mover.

A sleepy little town that had the greatest landslide in North American history fall on it.

A herd of colorfully painted bovine statues can be found in the middle of "cowtown."

Despite being dead since the 1970s, this Canadian tree is kept upright and intact by adoring locals.

Home of Howard Hughes' Spruce Goose.

The magic's in the hole!

The second largest waterfall by volume in the U.S., Willamette Falls is outdone only by Niagara in the amount of water that is pushed northward.

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