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

This coffee shop lies hidden beneath a historic church.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

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

When it opened during the final years of the embargo, all the drinks and cigars were free.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

During the Industrial Revolution this “Temple of Invention” was full of intricate miniature machines and gadgets.

Franciscan monks created a facsimile of the Holy Land for North Americans who couldn’t afford the trip overseas.

Home to items never before seen by the public.

One man's remarkable private collection of art from around the world.

A windswept necropolis carved into the rocks overlooks the "most Portuguese town in Portugal."

This once-forgotten oasis in the middle of Lisbon was first created over a century ago quite by accident.

You can cross from one country to another in a single hop on this little bridge.

One of the largest Roman settlements in Portugal.

"Portugal's Stonehenge" is made up of nut-like stones aligned with the heavens.

Dead weights honor the dead of Portugal's fishing industry.

Located in the thermoelectric factory that once powered the entire city, this Portuguese museum is shockingly fascinating.

This abandoned five-star hotel is now a five-star urban exploration destination.

The verdant mossy ruins of a Franciscan monastery lie in the remote Sintra hills awaiting exploration.

An abandoned mine now resembles a post-apocalyptic landscape of derelict buildings and blood-red pools of water.

A stunning 18th-century site where pilgrims ascend by a series of punishing stairs only to return via funicular.

This gaping hole in the middle of a remote mountain lake looks like a portal to another dimension.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

A submerged village appears when dam levels drop.