This little-known relic crypt holds stolen parts of a Roman Empress.

"In the Dark" Restaurant in Paris offers dinner in complete darkness.

Once the local rulers had gone these enchanting ruins housed common folk in an almost real life fairy tale.

Captain America, Sub-Mariner, and the Human Torch were all born in this art deco Manhattan masterpiece.

This study room in the New York Public Library saw the creation of one of contemporary America's greatest traitors.

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.

This unmarked and unloved Manhattan subway grate created one of the most iconic images in American cinema.

The name of this famed hospital was once a byword for the horrors of medical and psychiatric care.

During the 19th century, you could pay for violence off a prix fixe menu on this Manhattan street.

The oldest operating apothecary in the US has treated everyone from Thomas Edison to Mark Twain.

This impressive Boston holy house is the American mecca for Christian scientists.

A famous songsmith's custom piano, dubbed "High Society," is hidden just out of sight in one of New York's finest hotels.

A strangely angled West Village home is the only monument to an explosion that took the lives of three American revolutionaries.

A Manhattan courthouse hides a small but scathing memorial to Holocaust injustice.

This seemingly unremarkable boulder is said to bear the hoofprint of the devil himself.

Spinning silently in the lobby of an Art Deco masterwork is a massive vintage model of the Earth.

A miniature rainforest is growing inside of a Midtown Manhattan office building.

A tree that grows parallel to the ground was declared Brooklyn's "crowning curio" by the poet who saved it.

Collapsing castle on the Hudson river was once the storage site of military surplus business.

Twice a day one of these tragic bronze mariners drowns with the tide to remember all those the sea has taken.

Amid the marketing blitz of modern Times Square is an elegant holdover from its showbiz glory days.

This Wall Street bar was once a hub of revolutionary activity where Washington famously bid farewell to his troops.

Brooklyn's most iconic restaurant, resurrected.

The gilded vestiges of a sterling department store can still be found in a Brooklyn shopping center.