The second-longest continuous wall on the planet protects a hidden secret in the deserts of India.

Once an indicator of social class, the color blue has come to define this city on the edge of the Thar Desert.

The 953 windows undoubtedly make this the world's most beautiful screened porch.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

Thousands of exquisitely carved stone water storage wells, hundreds of stone steps fill this exquisite medieval stepwell.

Centuries-old bridges grown from tangled roots.

A French valley with forests so lush it was nicknamed "the Small Amazonia of the Pyrenees."

If they push on just the right spot, even the weakest person can move this titanic boulder.

A swath of France so devastated by war it is still forbidden to go there.

Bits of architecture from a town destroyed in World War I now decorate this hotel garden.

The Church of the Annunciation was carved into the face of a cliff, just like the rest of the town of Haute-Isle.

The deserted pirate-themed restaurant still entices explorers.

There has been an astronomical clock on this spot since the 14th century.

A chapel on a volcanic core, marking the end of a successful journey.

This is what trains will look like after the zombie apocalypse.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

Sleep in a climate-controlled plastic bubble for the night.

A Gothic cathedral created from volcanic rocks.

The largest underground church in Europe.

This natural French spring has been turned into a magical grotto by Roman and medieval constructions.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

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

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.