The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

A hidden "place of interment for gentlemen."

Blighted Irish field and the ruins of a 19th-century cottage on the edge of urban Manhattan.

One of nature's most well-scheduled phenomenons resides in Wyoming's Yellowstone National Park.

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

The world's largest mountain carving could fit all of Mount Rushmore inside it many times over.

A hollow cement depiction of time's inexorable effect on the human body.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Slyly buy a shake in the Parker Meridien lobby.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A very classy 1920s-era bar right in Grand Central Station.

Popular tourist destination where witches in dark hats sell dried llama fetuses for good luck.

This sculpture by artist Fritz Keonig survived the 9/11 attacks and now stands as a monument to the victims.

This massive redwood tree has a hole in the base big enough to drive through.

The subtle science of a master molecular gastronomist.

A once grand hotel is being retaken by the wilderness it once capitalized on.

A pair of slides and a tree-lined stair corridor have been an urban oasis for nearly 40 years.

This historic "City of the Dead" lies prominently in the center of New Orleans' famous Garden District.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Op-art architecture designed for happiness.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

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

San Francisco's newly reopened hands-on science museum.

The most visited, and possibly most controversial, museum in Germany.