Beijing's expansive subterranean hiding spot now crumbles away as a tourist destination.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

This immaculate and historic water garden culminates in a massive stone dining table with an inset fountain for chilling the wine of the Cardinal's guests.

The former locus of Boston's high culture has been shuttered and buried for over 70 years.

This modern museum of Mediterranean culture is surrounded by a surreal concrete honeycomb.

A devastating booze inferno poured through the streets, claiming several victims who drank it.

A restored Pittsburgh house of God has been converted to a marvelous house of suds.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

Barely visible foundations remain where Stow Lake’s “observatory” once welcomed visitors.

A 200-year-old collection of oddities and medical paraphernalia.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

The oldest pub in Ireland may also be the oldest surviving bar in the entire world.

Artifacts of whaling, with both its perils and adventure, are housed in this museum in a former candle factory.

The New York hotel where tragic visionary Nikola Tesla spent his final hours, destitute and alone but for the pigeons.

A peace symbol in Northern Ireland is among the world's largest hedge mazes.

The life of one of FDR's possible mistresses is preserved in her palatial Hudson Valley mansion.

On the top floor of an upscale department store stands a lavish restaurant housed in a replica of a luxury French dining car.

Nicknamed the "Museum of Horrors," this French anatomical collection has been fascinating visitors for over a century.

This former Roman Catholic Church still contains the embalmed hearts and organs of 22 popes.

An ultra-modern vista that has been featured in so many films the house is a celebrity in its own right.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

One of the oldest and certainly best preserved Cistercian abbeys still in existence.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This centuries-old Italian chapel hangs midway down a sheer cliffside.