The walls of the iconic dome are hollow and have a secret stairway.

The sweetest graveyard in the world is filled with headstones for dearly de-pinted ice cream flavors.

Visit the monolithic tomb of America's most famous general.

A sign at the end of the Santa Monica Pier marks the traditional end of the legendary American highway.

A cabin completely covered in coffee mugs, where visitors are welcome to leave one of their own—if they can find an empty nail.

The land is home to swimming ponies and a legendary 18th-century treasure.

Housed in a century-old building, this museum's dedicated not just to soft drinks, but to the free enterprise system.

An artist's cute bronze subway sculptures belie his violent artistic past.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

An abandoned quicksilver mining town surrounded by the Big Bend parks.

Visitors can walk over the largest concentration of Columbian mammoths to have died from one event.

Memorial of the Salem witchcraft hysteria in the town of Danvers, where it all began.

One artist's love letter to his city and its citizens plays out across dozens of bright murals painted on the sides of decrepit buildings.

This unlicensed collection of fast-food memorabilia sits on the site of the first ever McDonald's restaurant.

A lovely aquatic park built by a one-armed Civil War veteran who made a fortune from lotuses.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

At this Denver landmark, the meals are compulsory, the sopapillas are complimentary, and the insanity is everywhere.

A multi-storied adobe complex has been inhabited for more than a thousand years.

The site where Poe "in great distress, and ... in need of immediate assistance" likely died.

Macabre headstones carved with winged skulls, dancing skeletons, and pithy reminders of impending death.

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

One of the oldest living oak trees in the Southeast.

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