A chilling disappearance (and rescue) of a child uncovers a geological mystery.

The remains of a massive blast furnace in what was once one of the country's largest iron-producing regions.

The only remnant of a small mining town is an abandoned railroad tunnel that is steeped in ghostly lore.

Rare recess caves fill this unbelievably beautiful Ohio park.

Dine on dumplings at the oldest dim sum restaurant in New York.

Avoid gangster interaction while window-shopping.

A Hawaiian stairway to heaven—that you can't climb.

Hidden in Central Park's Ramble is a troublesome cave buried just beneath the surface.

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

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

The 28-foot granite map plots the locations of 40 theaters in New York City.

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

A popular European tradition makes its way to the states on one of America's most famous bridges.

The enormous 250-room Vanderbilt mansion conceals hidden doors and secret passageways.

Classy up your Big Mac with bow-tied servers and chandeliers at the world's fanciest McDonald's.

Strange physical sensations and optical contradictions keep visitors coming back for more.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.

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

The world's longest known cave system.

After a water tower painting was accused of being an ad, a simple fix was made that gave the city a motto.

Kentucky, Tennessee, and Virginia meet at this point in the Cumberland Gap.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

This presidential tomb was not dedicated until years after Harding's death due to personal controversy.

World's largest Christmas store.