Touching mementoes from those who didn't make it back from World War I still hang in one of New York's oldest bars.

A prohibition era watering hole for the police.

Once the tallest building in the world and the site of “the highest dinner ever held in New York” this building now holds the most expensive penthouse in the city.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

This elaborate towering structure was once famed for its revolutionary height.

A blend of art, antiquities, and Americana fill this museum, surrounded by whimsical, enchanting gardens.

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

This high point in the Great Smoky Mountains is said to be home to the chief of all bears.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

The secret city built by the Manhattan Project.

This replica of the Greek structure is in the heart of Nashville.

Once one of the largest producers of pig iron in the world.

A 56-foot tall statue of the god of fire looks out over Birmingham, Alabama.

Former villa and estate of James Deering developed to preserve native tropical forests.

No telescopes, no power, no gift shop: The Observatory of Chichen Itza, one of the world's oldest observatories, takes astronomy back to basics.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

This giant head is all that remains of a once proud statue that survived an earthquake but not a fall off of a wagon.

The last remaining relic of San Francisco's glittering 1915 Panama Pacific Exposition.

On holy holidays, Israel's second president used this room atop Mount Zion as a refuge to read the Torah.

The only quarter of the Old City not dedicated to a major world religion.

Neighborhood in Jerusalem is home to the ultra-orthodox haredim.

A "miracle" that seems to produce more holy fistfights than holy revelations.